Luxury Sedan Comparison Final Round : Mercedes-Benz C-Class v BMW 3 Series v Volvo S60

The Mercedes-Benz C-Class was Australia’s favourite luxury car in 2013. Perhaps a more impressive fact, however, is that Stuttgart’s mid-sized model outsold every mainstream medium car except the Camry and Mazda 6. It’s fair, then, to call this a significant volume car – as is its decades-old arch enemy, the BMW 3 Series, which matched that last feat.

If you’ve been following CarAdvice the past week, you’ll know we’ve taken a slightly unorthodox approach to the arrival of the new, fourth-generation C-Class – running two previous comparison tests to determine the best candidates to challenge Stuttgart: both from the traditional rivals (Audi A4, and 3 Series) and the alternatives to going German (Infiniti Q50, Lexus IS, and Volvo S60).

If you’re catching up, the title of this comparison reveals the outcomes of those tests.

Mercedes-Benz Australia is currently in aggressive mode. The pricing and equipment of its new wave of compact cars means cars such as the A-Class can’t be imported in big enough numbers. (And at July 2014 it was even outselling the outgoing C-Class.)

It’s clear the company has no intention of surrendering the C-Class’s No.1 sales ranking. While pricing has crept up fractionally, equipment more than compensates.

Take our test car here: the C250 petrol that costs $68,900 and, with its C250 diesel counterpart, will account for about half of C-Class sales.

It has technology as standard that makes it seem like a baby S-Class in more than just appearance.

There’s radar-guided cruise control, blind spot monitoring, semi-automatic parking system, cross traffic alert (for aiding the reverse out of a front-in parking spot), and a lane keeping function that can steer the car for you on freeways.

That’s on top of inclusive features such as LED headlights and daytime running lights, front and rear sensors plus rear-view camera, ambient cabin lighting, 19-inch alloy wheels, leather seats, satellite navigation, power adjustable steering column, rain-sensing wipers, electric front seats, one-touch electric windows and auto-closing boot lid.

Add it all up, and Mercedes says the new (W205) C-Class offers an extra $10,000 of value over its W204-codenamed predecessor.

BMW’s immediate riposte has been to close the equipment chasm.

The C250’s direct rival, the 328i, still costs from $69,400 despite the addition of new gear worth about $6000.

Standard features now include keyless entry and hands-free tailgate, rear-view camera, bi-xenon headlights, semi-auto parking function, head-up display (still optional on the C250), and camera-based lane departure and forward collision warning systems.

It’s still advantage Mercedes on the tech front. And our non-German contender here, the Volvo S60 T5 Luxury, can also lay claim to be a better match for the Benz in this respect.

The Volvo misses out on standard digital radio, but it does come with internet connectivity that syncs seamlessly with your phone, and allows you to use apps such as TuneIn web radio.

You then need Volvo’s $5000 Drive Support Park, though this only helps to bring parity in pricing ($67,015) when the T5 Luxury starts from just $59,890.

The pack also gives the S60 some one-ups even over the Benz: headlights that can switch automatically between main and high beam at night if oncoming traffic is detected (optional on C250), and Road Sign Information that uses a camera to read speed limit postings and relay them to the instrument panel. (Watch our video to see how it works.)

It forms part of a smart TFT display brought in from the V40 hatch, while the S60’s main, 7.0-inch Sensus infotainment display serves up rich colours and is neatly inset into the dash.

Volvo opts for more buttons than the German pairing, and it takes a bit more time to get accustomed to their positions and functions – important for using on the move.

There’s no better menu-operating system to use on the go than BMW’s iDrive system, though. Once mocked by rivals and media alike, constant evolution has made it the class's most effective infotainment.

Its 8.8-inch display, rising out of the top of the centre stack without upsetting the harmonious dash design, is the biggest, widest here, and the large rotate-and-click dial on the centre console can be used while just looking at the screen. Shortcut buttons complete the high user-friendliness factor.

The C-Class’s Comand system also uses a rotary dial though in conjunction with an encroaching touchpad (which get plenty of space with the car’s gearshifter moving to become a trad-Merc steering wheel stalk). You use a combination of both to select modes/functions, and there’s a handwriting function, though the touchpad’s responses could be quicker.

As in the S-Class, operating Comand can feel like a more convoluted process compared with iDrive, while BMW’s nav system not only presents better but delivers more precise routes and instructions.

If you’re an Apple-phile (like our founder Alborz), you’ll love the iPad-mimicking Comand display – though whether you have the standard 7.0-inch or optional 8.4-inch version, it is the most incongruous element of the interior.

The Volvo S60 actually boasts the tightest fit and finish, and revels in Scandinavian design flair, but overall it’s the mid-sized Mercedes that resets the bar for interiors in this segment. The C-Class’s classily curved and crafted cabin is guaranteed to hook buyers before they’ve even bothered with the test drive.

Throughout the cabin, there is unrivalled texture quality and tactility – the latter perhaps no better epitomised than by the almost-sensual window switches (just one cue borrowed from the S-Class limo).

The interplay of colours and materials – the latter selectable between wood veneers, gloss plastics or genuine metals – is also superbly judged.

Perception of quality isn’t exactly low in the 3 Series, though it does feel like a less expensive car compared with the Benz. The BMW is also let down in some details, with more obvious areas of beancounter interference. Its Mercedes rival

The C-Class doesn’t look any less luxurious in its rear accommodation. Legroom was deemed second only to the A4 overall, though its advantage was a small one considering it has the longest wheelbase (2840mm) in the segment.

And if you don’t want squashed toes, you’ll want those in front to raise their seat heights.

Above: BMW 3 Series (top) and Volvo S60 (bottom).

Rear bench comfort is high in each, knee space is also good in the S60 and 3 Series, while the BMW is a bit tight on headroom (as is the C-Class is you go for the optional panoramic sunroof).

All have rear seatbacks that fold in varying configurations, though the visible spare robs the S60’s boot of some practicality (unless you take it out, of course).

Cabin comfort is also influenced by ride quality, and the obsession of manufacturers’ marketing divisions with optional or variable suspensions means determining how well a particular car drives is a more complex affair these days.

Above: Mercedes-Benz C-Class.

It’s certainly the case with the C-Class, 3 Series and S60.

The Volvo on sports suspension (optional, or standard on R-design models) can be annoyingly jiggly and the damping is slow to settle the car over dips at higher speed.

On the regular suspension and smaller (18-inch) wheels propping up our T5 Luxury here, better body control and reduced (but still noticeable) fidgeting make it a more composed drive. There’s still some driver appeal here despite the S60 being the only front-wheel-drive car here. Nicely linear steering helps, though it can be a touch heavy at low speed, and the grippy standard 18-inch tyres are effective at putting the power down out of corners.

Conversely, you definitely want to tick the $2200 ‘Adaptive M Suspension’ option if you want your BMW 3 Series to live up to the famous ‘ultimate driving machine’ tag.

We find the Sport mode preferable to Comfort, still. It tightens up the 328i’s chassis to limit undesired vertical movements but without allowing noticeable intrusions from the road surface.

A surprise from this group test, though, is that the new C250 doesn’t ride particularly well on its standard steel-sprung suspension. We mention C250 specifically, as during the car’s official launch fellow tester Alborz found the C200 on the same suspension (with 18-inch wheels) more convincing.

Generally lumpy and prone to being noisy and jolting occupants, this hadn’t been our expectation after the superbly judged ride/handling balance of the previous model.

In the name of thoroughness (we were testing prior to the car’s launch and wanted to know the car inside out) we had three C250s all up. A diesel on standard suspension confirmed our thoughts on the C250 petrol.

Our third C250 sat on the optional Airmatic suspension, which can be manually adjusted for damper firmness via the Agility Select console switch (which otherwise changes steering, engine and gearbox response). It’s a $2490 investment that transforms the C250’s ride.

There’s still some inherent firmness due to the 19-inch run-flat tyres – and a $2685 AMG Line Package also brought a lowered sports suspension among many other extras – but the air springs bring much-needed isolation from road irregularities in the city, suburbs and country roads. And on the freeway the air-suspended C-Class glides over freeway expansion joints with just a little ‘whump’ where they’re actually felt thumping through the regular suspension.

Handling also benefits, especially if you switch out of Comfort to Sport, because where a steel-sprung C250 can skip over mid-corner bumps the Airmatic C250 is unruffled.

With either suspension, the C250 steers precisely with spot-on weighting, and the C-Class’s chassis – burdened by significantly less weight than the last model through lighter body construction – is beautifully balanced in the bends and aided by high levels of grip.

The electric steering of the new 3 Series doesn’t communicate with its driver like the hydraulic systems did in the previous two generations (E90 and E46), and neither is it as perfectly responsive to inputs.

It’s at its best in corners as lock is being applied, though, and it doesn’t prevent the BMW from retaining its status as the segment’s dynamic benchmark.

If you’re content to let your luxury car do more of the work for you, the new C-Class has the most autonomous-driving tricks up its sleeve.

On the freeway, Mercedes’ Distronic Plus radar cruise system (above) controls your distance precisely to the car ahead without having to touch either the brake or accelerator – and, like the S60, at any speed.

You can even go hands-free and let the Steering Assist (freakily) make little movements of the steering wheel to keep you within the lane markings.

A graphic will eventually pop up encouraging you to place your hands back on the wheel, though the system will continue to operate for as long as you dare even if you don’t.

There’s nothing like commonality in a comparison test, and each of our contenders here has agreed on a 2.0-litre four-cylinder engine with single turbos, direct fuel injection and stop-start, each mated with a conventional torque converter automatic transmission.

The 328i and S60 T5 even share eight ratios (to the Benz’s seven) and 180kW of power (to the C250’s 155kW).

Maximum torque of 350Nm is identical across the trio – and in each case spread across a handy engine range.

The S60’s torque plateau runs from 1500-4800rpm, the C250’s kicks in earlier at 1200 but ends sooner at 4000rpm, and the 328i goes the broadest with 1250-4800rpm.

BMW takes the performance honours. Its 5.9-second claim for the 0-100km/h sprint heads the Volvo’s 6.3 and Benz’s 6.6, and through the gears its turbo four feels the more muscular.

None of these engines will disappoint buyers in terms of refinement and pulling power, though they might for noise.

We have to get over the fact today’s 328i has lost the delectable note of yesterday’s inline-six-cylinder model (as well as crisp throttle response), but in return you do get an engine-gearbox combo that excels whether you’re driving slowly or quickly.

There’s no conventional automatic gearbox in the world currently that can swap cogs with a better combination of speed and timing than ZF’s eight-speeder.

As speeds rise, and the driver ups the ante by switching from Comfort to Sport modes on the vehicle settings, and the ZF ’box simply increases the sharpness of its responses without detriment to shift quality.

The S60’s new eight-speed auto is undoubtedly smooth though it offers fewer options for the driver’s intentions.

The only different mode – Sport – does little to sharpen throttle response and doesn’t over-ride the auto’s determination to change gear 500rpm before redline (even if you use the paddleshift levers).

The C250’s engine doesn’t feel quite as responsive as its rival fours here, while the upshifts of the Benz’s seven-speed auto aren’t the quickest. Even on slight inclines the auto didn’t seem to have the same confidence in the engine’s torque – sometimes dropping two gears.

The drivetrain is smooth, though, and it becomes enjoyably feisty if you select Sport Plus mode and use the paddles.

The C250 officially is also the most economical car here, with its 6.0 litres per 100km combined cycle comparing with 6.3L/100km (328i) and 6.4L/100km (S60 T5).

During testing, however, the BMW 328i returned 8.6L/100km – consuming exactly two litres less than both the C250 and S60.

Such a gap was unexpected, though a surprise in the Volvo’s favour is that only a few months ago it wouldn’t have been predicted to even make this final shootout.

Volvo’s ambitious moves to transition from semi-premium to full luxury brand haven’t always been convincing, but interior and drivetrain updates for the S60 have turned the Swedish sedan into a surprisingly worthy alternative to the Germans. It doesn’t hurt that it’s a decent-looking four-door, too, while its stylishly designed, impeccably finished and superbly comfortable cabin is only second to the C-Class’s interior in our view.

However, after our three comparison tests, featuring six mid-sized luxury cars in total, it comes down to an intensely close, blow-for-blow fight between the longest and greatest of enemies.

The 328i has the stronger performance and more intuitive auto, where the C250 has the leading on-paper fuel economy (though not on test). The 328i has the more intuitive and responsive infotainment interface; its equipment expansion was a crucial response to the Benz, though the C250 still has the advantage on technology.

Disappointingly, both need optional suspensions to be at their best, though at least the Adaptive M and Airmatic suspensions are relatively attainable at less than $2500 apiece.

Thus equipped, the 3 Series and C-Class boast the most consistently smooth drives in the class.

And it’s here where the Mercedes-Benz C250 feels most like an S-Class, seemingly satisfied to leave the 3 Series as the pick for buyers who want their mid-sized executive four-door to double as a compact sports sedan at the weekend.

While some occasionally intrusive wind and tyre noise informs you that you’re not quite in the eerily hushed realm of the bigger Benz, it's hugely significant that the C-Class comes standard with some of its clever tech that moves the game on. And while the heavy influence of the S-Class on the new C-Class's exterior design is obvious, it’s how the interior imitates the limo’s luxury ambience that marks another watershed moment for the segment.

If you’re looking for a 70,000 luxury car that can impart an instantaneous feeling of success, the new C-Class is the one.

Leasing estimates from Platinum Direct Direct, based at 6.03% with a 40% balloon to be paid over 60 months:

Model / RRP / Monthly repayment / Balloon

Volvo S60 T5 Luxury / $59,890 / $811.33 / $23,596

Audi A4 2.0T Ambition / $59,900 / $811.47 / $23,690

Lexus IS350 Luxury / $65,330 / $885.03 / $26,132

Infiniti Q50 Hybrid S / $67,900 / $919.85 / $27,160

Mercedes-Benz C250 / $68,990 / $934.61 / $27,596

BMW 328i / $69,400 / $940.17 / $27,760

Read the other two knockout rounds:

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