Audi S4 v Mercedes-AMG C43 sedan comparison

The S4 and C43 represent the entry point into Audi's and Mercedes-AMG's performance mid-sedan ranges. Are they merely facsimiles of their go-faster stablemates, or properly desirable luxo-sports Euros in their own right? And which one is the CarAdvice pick?

The old adage ‘speed costs, so how fast to do you want to go?’ applies more eloquently to its more-is-more motorsport origins than it does to the more complicated prospect that is premium road car ownership.

It’s sometimes easy to forget the a circa-$150k upfront investment for a low-four-second 0-100km/h return – not to mention ongoing mid-teen-per-hundred average fuel consumption expenditure – appeases the wants and means of only some buyers, though not all, when it comes to go-fast four-doors.

For some, the nameplates C63 S and RS4 aren’t merely a stretch too far financially but, realistically, a lunge unnecessarily high in useable performance.

The Audi S4 3.0 TFSI quattro Tiptronic Sedan and Mercedes-AMG C43 4Matic Sedan – to use their full names, just once – might seem the undercooked missing links between the have and have-not-quite-as-much, but let’s be realistic here: there’s less a link and more a canyon between the (currently wagon only) RS4 and an A4, and between a C63 S and a C250.

For instance, you could buy two C250s ($69,400) and still save $17k-odd on just one C63 S though, fittingly, doubling one C250’s horsepower figure (155kW) leaves you short 65kW of the (375kW) ‘63’. Not only is there ample room for Ss and 43s to exist, there’s plenty of real estate to get them ‘right’ in their respective makers’ model lines.

How ‘right’, and how nicely balanced and tempered the S4 and C43 are, is logically how they should be judged then.

Price and Specification

Price wise, the C43 sedan wants for $101,900 sans options and on roads, or a slightly high-skewed mid-point between C250 and C63 S. At $99,900 list, the S4 is couple of grand more affordable than the C43, a mere two per cent pricing disparity.

Like its Benz contemporary, the S4 is positioned mid-point, more or less, between the current $69,900 A4 2.0 TFSI quattro and, if track record is anything to go by, an estimated circa-$160k ask of a next-gen four-door RS4, a nameplate currently in short-term hiatus.

The six-figure tipping point is a crucial one in prestige Euro motoring. It’s far enough above the entry point for brand cache that premium-ness must be emphatically felt in depth of goodness. Conversely, it’s affordable enough to theoretically dodge price-lifting indulgence for its own sake.

Circa-$100k should, by and rights, be something of a luxury-performance sweet spot, not merely a place to inhabit ‘performance’ without the 'high-' prefix.

The good stuff fitted standard to both cars includes adaptive LED headlights, adaptive suspension, 19-inch wheels, 360-degree camera systems, heated electric front seats, leather trim, and comprehensively specified high-end infotainment and audio, though the complete list of features for either mid-sized German is too exhaustive to list here.

Audi claims a best-in-class 29 different safety and assistance systems (if you include gear such as electric handbrake, Drive Select and Dynamic steering), right down to first aid kits and hi-viz vests, it's a comprehensive suite.

Mercedes-AMG counters this with adding some incidental extras (tow-away protection, interior surveillance) to the exhaustive list of safety and conveniences already fitted to lesser C-Class variants.

Options? With its pearl effect Misano Red paint work ($1846), quattro sport differential ($2950), Technik package ($5600) and S Performance package ($5900), our $99,900 S4 becomes a $116,196 as-tested proposition before on-roads.

Meanwhile, Obsidian Black paint ($1990), Seat Comfort package (for multi-adjustment and heating, $1290) and Performance Ergonomics package ($4990) raises our C43 from $101,900 to $110,170 in the form you see here, before it hits the road.

The Audi gets some techy trinkets, but for every one that comes standard (the dynamic strobing indicators) there’s another that demands extra cost (Matrix LED headlights, aforementioned head-up display). The C43, with its standard panoramic glass roof and Burmester surround sound, looks slightly more comprehensive in the equipment stakes.

Ostensibly, though, the relative spec this pair boasts is separated by shades and degrees. How these shades and degrees stack up may well tip the win one way or another.

One area where this applies is perception and expectation, which brings us to badging, an area where each of these car’s makers has taken different tacks.

Today, Audi’s ‘S’ badge has identity, earned through providence born of a linage of mostly accomplished models upon which a solid reputation for the 'S' badge has been built. There’s no ‘A’ or ‘RS’ muddying the ‘S’ concept a great many buyers are now familiar with.

Right now, the relatedly newer ‘43’ has a tougher job to sell. The C43 is certifiably Mercedes-AMG branded in name if, in many eyes, not quite so in concept or, arguably, execution.

Sure, ‘43’ is a resurrected AMG nameplate (from W202 C-Class), if one a little lost in the minutiae of the history that's overshadowed by the more heroic ‘63’ nomenclature headlining AMG's most recent chapters.

Not helping 43 badge cache is that this car was a Mercedes-Benz branded C450 AMG, under the AMG Sport banner, figuratively yesterday, which doesn’t help dispel preconceptions that the C43 is a bit, well, AMG-lite. Be it the case or not.


Glass half empty or half full, this pair arrives at pretty much the same point on the public grid. Each is powered by a 3.0-litre V6 – biturbo for the Benz, a novel single-turbo set-up for the Audi – with each plying its energy via a conventional torque converter automatic and all-wheel drive.

The S4 boasts 260kW and 500Nm via eight forward ratios and promises to hit 100km/h from a standstill in 4.7 seconds.

Meanwhile, the C43 produces a superior 270kW and 520Nm, uses nine speeds and is claimed to reach triple figures some 0.2sec slower. (Correction: both cars have claimed 4.7sec acceleration times.)

Sub-fives isn’t hanging about. In fact, Audi reckons the S4 sedan is as quick to 100km/h as the old, naturally aspirated V8 RS4 Avant. Thanks largely to construction trickery, this S4 is claimed to be 75kg lighter than its predecessor, or a still-portly 1705kg kerb.

The eye-opener is the C-Class, which, despite being encumbered with all-wheel drive and at 1690kg kerb, the C43 is some 40 kilos more lightweight than the rear-driven C63 S (1730kg kerb). So much for 4Matic being the package’s anchor. AMG’s claim that the more heroic rear-driver is a full seven tenths quicker to 100km/h is something I’d like to witness with my own eyes…

On the road

Dial up Dynamic (Audi) or Sport+ (AMG) drive modes and each has an assertive shove you feel in the pit of your stomach though they aren’t quite fiery enough to bristle the arm hairs. When chasing redlines, the C43 is perhaps a little gutsier down low, the S4 more tempered and linear, and not much separates measuring by the seat of the pants.

Each provides unstrained progress marching forth that are both noticeably more effortless and gusty than their humbler turbo-four stablemates, if appreciably less head-pinning than you’d reasonably expect from RS or V8 AMG stock. Potency wise, they’re on the money for their luxury-performance pitches.

Neither stirs the mojo pot with soul or vigour, be it visually or sonically. Each has neat, slightly muscular executive presence that’s more sport-tinged than thoroughly massaged. Either car could be a humbler A or C variant with an optional sport enhancement package ticked.

The S4 is louder than a Euro-spec I drove last year, though it’s a bit of bass-y undertow rather than proper rumble. Ditto the C43, which is slightly less polite than the Audi but only finds its rorty bark once the right pedal is pinned to the AMG-logoed floor mats.

Peg the pace back and the Audi is the more resolved offering. Opting for true automatics, rather than dual-clutch automated manuals, really suits the tempered performance brief, though the S4’s eight-speed is smoother and more intuitive at low speed and under a modulated part throttle.

By contrast, the AMG-fettled Benz-spec nine-speed (not the bespoke AMG ‘63’-spec ‘MCT’ seven-speed) can be grumpy around town, even in lazy Comfort drive mode, pausing and thudding in an unrefined manner at times.

Each car has marked degrees of Jekyll to Hyde in character transformation though it’s the Audi where each persona is more convincingly well rounded. The quiet refinement of Comfort is virtually faultless, yet it doesn’t drop the ball with on-tap response and drivability at the twitch of the right foot. Meanwhile, its Dynamic mode is never too highly strung, and there’s a nice roundness to its muscle and abilities.

The C43, in isolation, is also a sanguine cruiser though its feel and responses are patently more sports flavoured in its own Comfort mode. Its steering is heftier at low speed, while its slightly too-sharp throttle, pronounced low-rpm toeiness and light pedal springing leave it constantly ‘pulling against the leash’.

Ride wise, despite the Ride-Control adaptive damper set-up, the C43 is slightly fidgety and tends to thump more over square-edged road imperfections than the Audi, complete with that strange ‘wobble’ evident in many a contemporary Benz where road lump and undulation translates directly into annoying body roll. Despite this characteristic sportiness, it’s a little lazier than the Audi in general around town response.

Despite these criticisms, to live with in an urban jungle, this could well be the current C-Class struck most sweetly. There’s none of the under-baked, lightweight lethargy of Mercedes-Benz-branded Cs, none of the punishing hard edges, ostentation, gruffness or wallet-punishing thirst that C63 fans consider as true grit but are tiresome to live with.

The S4, also fitted with adaptive suspension, is less heroic in the sensory experience but offers more depth throughout. It rides nicer and with less suspension noise then the C43, has more disciplined damping yet sits flatter and more confidently and doesn’t pitch around across road imperfections.

Both cars have exceptionally good 360-degree camera systems, with switchable views via the infotainment screen and sensors front and rear to complement the cameras. And each car's elaborate camera and sensor system is tied to smart and very handy parking and traffic monitoring conveniences, such as cross-traffic alert.

However, neither German sedan gets full marks for faultless active safety intervention. Audi Pre Sense forward collision warning, for instance, likely chimes in during a jaunt across Sydney town in unwarranted situations. And both have corrective steering intervention that'll have you diving for the off switch sooner rather than later.

Each car packs enough technology to go, stop and steer itself towards the end of a semi-autonomous pipe dream. Sure, neither car claims to offer driving autonomy, though each comes with the suggestion to be able avoid almost any pear-shaped mishap in almost any driving situation.

With their active intervention systems, neither car overcomes false positives or situations – running off the road, say – where you expect intervention that never arises, where the driver must dive for the controls to avert disaster.

Half of the problem with smart tech application in any high-end car is that the car simply doesn't make it clear enough to the driver whether its cleverdick systems are even functioning or not, or if indeed they need to be proactively switched on.

From testing both cars out in a variety of driving situations, the conclusion is that their active intervention and guidance systems – lane keeping, adaptive cruise with stop and go – aren't executed and calibrated to the point of offering foolproof surety all of the time.

In the corners

The Audi's steering is lighter, though it's slightly more direct, clearer and easier to use everywhere from three-point turns to bombing through fast sweeping curves. For balancing a broad range of driving situations, it’d have to be one of the finest premium sedans out there, full stop.

Punted along an Aussie backroad – or, as I discovered last year, across a European Alpine pass – the S4 mightn’t be the sharpest tool in the shed, but it does blend grip, poise and dynamic purpose exceedingly well.

It generates a lot of lateral adhesion from its four 245mm 19-inch Hankook Ventus S1 Evo tyres and provides a nice neutral dynamic character, though it is a little difficult to discern what exactly the ($2950 optional) quattro sport differential brings to the handling party at spirited, if sensible, on-road speeds.

Sat on unequal 225mm front and 255mm rear Dunlop Sport Maxx rubber, the C43’s is understandably less evenly balanced in grip across its axles, with a slightly less assertive front end if you push on hard, though it does track supremely well and with plenty of accuracy provided you don’t attack the public road like racetrack.

Like the Audi and other fine systems, the AMG’s all-wheel drive is transparent to the point of invisibility – there’s no discernible shuffling of torque between axles or wheels.

Interestingly, the Audi system delivers a 60-per cent rearward torque split under normal driving, though up to 85 per cent of torque can be fed to either axle.

The C43 sends slightly more torque rearward, a fixed 67 per cent, which corresponds with a slightly more rear-driven feel to the dynamic experience, though the experience is one of constantly assertive drive with the absence of wheelspin, one without any interest in power oversteer theatrics.

Let’s face it: if you’re up for a loose and lively game, neither of these sedans make list-topping teammates. But the trade of tail-swinging frivolity for brisk, surefooted and ironclad passage even in the most unfavourable conditions – such as the monsoonal rain Sydney copped in March this year – is one many luxo-performance car buyers are undoubtedly willing to make.

For user-friendliness and competency across a slippery mountainside, though, the Audi is ahead, if by measures of shades.

The S4 also gets six-piston front brakes against the C43’s four-piston units, and while actual stopping power differences between the two are negligible, the Audi's do have less initial bite and are a bit easier to modulate during the heat of particularly hot moments.

If there's one frustration in the Audi driving experience it’s the sailing mode, which decouples the engine under a constant or decelerating speed to save fuel, which is good, but also clocks on during some gentle descents, allowing speed to creep upwards – at times adding 10km/h above nominal road speed – before it deactivates to initiate engine braking.

Speaking of fuel, Audi claims a more favourable 7.7L/100kms combined against 8.2L for the Mercedes-AMG. The only time either came close were long stints on the motorways with their adaptive cruise controls set to the speed limit. Around town, consumption range for each hovered around the 12L mark, which is decent but hardly great.


The Audi’s all-round depth continues in the cabin. Its pneumatically adjustable S Sport seats blend comfort and purpose much better than the smart-looking if deep-bolstered, stiffly-padded C43 seats that pin your torso, have next to no shoulder support and provide little in the way of long-haul or around-town comfort.

The Audi’s diamond-stitched Nappa leather trim is noticeably more supple than the hardier AMG trim, and there’s a bit more richness and diversity of materials abound. Thing is, Audi charges extra ($5900) for pretty much all of the nicer stuff bundled up as its S Performance package.

The more conventionally styled C43 treatment feels cosier than the airier, more modernistic S4 take, though favouring either is a matter of personal taste. They trade blows in most areas.

For instance, the Audi wins on slicker switchgear and generally nicer textures; the AMG wins on nicer metallic detailing and richness of materials (bar the aforementioned leather).

Both are ergonomically fit bar minor markdowns here and there: the Audi persists with a misplaced dead pedal and a lack of front seat under-thigh support, the AMG's driver’s seat bolsters forever foul elbows during large steering inputs.

Neither lacks for bells and whistles and there’s enough addenda to remind you of your $100k investment, such as head-up display (standard only in the C43), the S4’s Virtual Cockpit digital instrumentation and the C43’s neat ‘output meter’ infotainment subscreen, which displays engine power and torque output in real-time, in case you were curious about how many kilowatts it takes to maintain 110km/h on cruise control (answer: about 35).

Realistically, though, apart form the seats, steering wheels and minor addenda, little separates the cabin treatments between this pair and more modest A and C-Class variants.

In fact, the AMG’s seats and wheel (and upgraded exhaust) want for an extra $4990 option called the Performance Ergonomics package, which a highly questionable upgrade given that, powertrain apart, much of C43's $30k-odd premium over C250 is already somewhat justified through various standard AMG addenda such as seats, steering wheel and exhaust...

One handy area where the C43 pulls a win is in shortcut buttons. The Audi requires digging through menus to adjust settings for systems governed by drive modes, specifically engine, suspension, steering, sport diff, engine sound and adaptive cruise protocols.

Meanwhile, the AMG does likewise, providing its own Individual mode to pre-select engine, suspension, steering, stop-start and air-con settings, but you can also adjust transmission, suspension and exhaust using dedicated buttons on the centre console, or turn conveniences such as Steering Pilot or active lane-keep assist on or off with a single buttons on dash fascia.

The C43's COMAND infotainment system really is a cut about the Audio 20 system in lesser Benzes, though it maintains the clunky user interface of the breed.

That said, the slicker MMI Navigation Plus system in the S4, with its multi-button control, also requires some familiarisation to extract its best.

Each demands some frustrating submenu digging to adjust settings, and each has a touchpad console controller to input, say, addresses into the sat nav.

In the second row, the Audi gets more sculpted, form-fitting rear seating compared with the flatter AMG arrangement, and given cabin width and tailshaft tunnels, both cars struggle providing comfort for three adults in back.

If anything, the C-Class format is slightly narrower for shoulder and headroom, and the Audi has fractionally more knee-room.

The AMG also gets no rear outlets or air con control, whereas the Audi offers a single 12V and a proper three-zone climate with rear temperature adjustment.

Both offer split-fold rear seating – 60:40 (kerb-side) for the Audi, 40:60 for the AMG – allowing extra load convenience to their comparable boot spaces, where the Audi alone offers handy metal tie-down points and a luggage net.

While the S4 gets a spacesaver spare wheel and the C43 just gets an inflator kit, the latter is the only one with a powered boot lid.


Any disparity between the two premium luxo-performers in equipment, price, the obvious value equation between the two and sheer performance is marginal enough to not push a winning result one way or another.

And although they're characteristically different in handling dynamics, the levels they play at are essentially line ball, each favouring one subjective driver whim over another.

Where the S4 ekes out the victory is in providing a better-rounded and evenly-tempered experience when balancing back road punting, grand touring and around town driving. It's a little more polished on balance, a little more resolved as a package.

Should you buy the Audi over the AMG?

Not necessarily. Buyers who happily trade some all-round resolution and polish for an extra layer of machismo in the vibe stakes may well find the C43 more to their taste. In fact, in isolation, the Audi has ample feel-good character, and the AMG feels supremely refined and evenly-tempered across all driving disciplines.

Neither pile on muscle or performance vibe and for some buyers that's part of their appeal. In fact, they're tempered and accomplished enough to be considered not so much as missing links, but perhaps jack-of-all-trade sweet spots in their respective A4- and C-Class-derived mid-size premium ranges.

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