Now in its sixth generation, the BMW 3 Series is still the luxury German brand’s bread-and-butter model in Australia, and at $91,400 (before on-road costs), the BMW 335i remains the flagship in the premium mid-size line-up, at least, for now. BMW aims to release the more powerful ActiveHybrid 3 towards the end of 2012, which will succeed the 335i as the BMW 3 Series range-topper.

Prior to its release in February, there were more than a few BMW fans concerned over the new F30-designated 335i’s growth spurt since the previous E90 version.

But BMW pulled off an impressive feat – despite increasing the length and width of the new model, it reduced the overall weight by 30kg to 1520kg and even managed to introduce a more generous roll call of standard kit.

Its performance has improved too. The new BMW 335i sedan is capable of sprinting from 0-100km/h in just 5.5 seconds – shaving three-tenths off the previous model’s time.

Fuel consumption and CO2 emissions have also fallen, despite identical engine outputs of 225kW and 400Nm from the carried-over 3.0-litre turbocharged six-cylinder powerplant.

BMW claims a combined fuel consumption of 7.2 litres per 100km (down from 9.6) for the 335i sedan and CO2 emissions of just 169g/km (down from 231).

The BMW 3 Series has, for the most part over the past 29 years, set the benchmark for compact sports sedans ever since it first joined the BMW line-up in 1983 as a second-generation model.

For as many years, the 3 Series sedan has had the wood over its rivals in the performance arena with its balance, poise and the connection it makes with those lucky enough to be behind the wheel of the high performance models.

But these days, the BMW 335i flagship faces increasing competition, from the likes of the Audi A4 3.0-litre TSFI quattro, Mercedes-Benz 3.0-litre C300 and the Lexus IS350 all vying for the top spot in this high-profile, performance-based niche segment.

Equal threat can be found lurking in BMW’s own stable with the superbly balanced, but less powerful, BMW 328i. It shares the same 250km/h top speed with the 335i, but is slightly slower off the blocks, needing 5.9 seconds to complete the 0-100km/h sprint.

There’s also a significant premium to pay for the extra grunt delivered by the range-topping 335i over its 328i sibling – $27,300 before on road costs are added.

But there’s a lot more to the top-of-the-line BMW 335i than a few tenths of a second in the acceleration stakes.

For starters, it’s well stocked with more premium-grade standard features including 18-inch light alloy wheels, larger 80mm dual exhaust tips, a Harman Kardon 16-speaker sound system, Bluetooth connectivity with voice control and album cover display, an 8.8-inch high-resolution screen with Navigation System Professional and internet functionality through the iDrive controller.

As well as the five 3 Series sedan variants available in Australia, buyers can also choose between three optional ‘Line’ packages: Modern, Sport and Luxury. These finishes are priced from $1000 to $4900 depending on the variant.

There’s still a bewildering array of options on offer for the 3 Series, as the three specification lines convey more of a style package than a traditional options pack.

To complicate matters further, there’s also an M Sport Package available for all 3 Series sedan variants except the 318d. Key features include M Sport suspension, M leather steering wheel, BMW sports seats and many other performance-oriented goodies.

We tested the BMW 335i Sport Line, which includes highlights such as a double-spoke version of the 18-inch alloy wheels, ambience lighting, exclusive high-gloss black trim both inside and out, ‘BMW Sport’ doorsills finishers, black chrome exhaust tips, and several contrasting upholstery options including Dakota black leather with red highlights.

The cabin of 335i Sport Line is a nice place to be. The fit and finish is first class from top to bottom with a collection of quality look and feel surfaces married to an uncluttered centre stack and instrument cluster.

While we love the contrasting twin stitch on the upholstery and steering wheel, we’re not fans of the plastic red strip that spans the dashboard – a little too kitsch for this reviewer.

All the important things we have come to expect from a BMW sports sedan are represented here in the 335i, additional to the fact there’s also room enough for four adults and their luggage.

It starts with some of the most comfortable and supportive sports seats in the business. They simply lock you in to the perfect driving position as well as any non-harnessed pews could ever hope to do.

The three-spoke leather steering wheel is special too. It’s thick, but not too thick, and its leather wrap is specially grooved for extra feel and tactility for those hard charging moments (and there’ll be plenty of those).

Hit the well-hidden starter button (on the left-hand side of the steering wheel) and the 3.0-litre TwinPower Turbo engine plays a smooth, up-tempo tune with an underlying growl as back up.

There’s no dual-clutch transmission for the 335i, but what there is instead is a very refined, quick-shifting eight-speed automatic gearbox that does a fine job imitating the haste of a dual-clutch unit.

Our BMW 335i was also fitted with the optional Adaptive M suspension, providing some additional firepower with the Sport plus setting.

In this mode, when hard on the throttle, expect the BMW 335i four-door family sedan to instantly morph into a highly aggressive performance car with lightening-fast throttle response and shift times and a lot less nannying from the dynamic stability control system.

Less thrilling – and at the other end of the dynamic scale – is the Eco Pro setting. It sits below Comfort and Sport modes, and effectively optimises throttle response and the automatic transmission with the goal of achieving the lowest possible fuel consumption.

It’s not the most exhilarating of drive modes and, frankly, is best left for long stints on the freeway. Comfort mode is ideal in light to moderate traffic conditions, but switching to the more aggressive Sport setting is advisable the moment you get clear road.

There’s a decent exhaust note from the BMW 335i at mid-range, but it gets a little too metallic and raucous above 5000rpm. The engine is actually best heard from outside the car, as not a lot of the good stuff is channelled into the cockpit.

The all-electric steering is a delight in this setting. It tightens up on the straight-ahead and is quick to respond to rapid changes of direction. There’s loads of feedback and a real connection between the tyres (despite being run flats) and the steering wheel.

The chassis balance and suspension geometry of the BMW 335i is outstanding. The adaptive M suspension minimises body roll on turn in (it’s minimal), backed-up by the 10mm drop in ride height that’s also part of the package.

There’s plenty of grip all round, although you can feel the extra weight of the 3.0-litre six over the front end compared with the 2.0-litre 328i, which feels more agile in the twisty bits.

Ride control is equally superb. The BMW 335i manages multiple different road surfaces with such expertise that the car never feels unsettled regardless of the pace. Even with Sport Plus selected, the suspension irons out all but the most severe potholes.

In Comfort mode the ride only improves further and with greater pliancy and a less urgent throttle response.

For six generations BMW has been carefully evolving and honing every facet of the 3 Series and has again pulled it off with a more capable and stylish version than its predecessor.

The F30 BMW 335i is an exceptional car. Superbly balanced with predictable handling, and best of all it goes hard. It’s a true sleeper that doubles as the perfect executive sedan for the weekend enthusiast.