Mercedes-Benz C300 vs BMW 428i

What's the difference?

Over five decades, the Mercedes-Benz C-Class has pivoted between mastery and mediocrity, and all-too-often relied on that three-pointed star up front to win over buyers.

Thankfully, the W206 is one is one of the better generations. It's easier on the eye, comfier to travel in, more intuitive to use, safer across the board and a huge improvement to drive. On the evidence of the C200 and C300 launch grades, there's newfound depth and consistency to savour.

Sure, prices have gone up, the C200 could use a bit more power, the steering could benefit from a bit more feel, the odd build-quality glitch made itself heard and there's a fair bit of road noise at times, but overall, the C-Class now deserves to be at the top of your luxury medium sedan shopping list.

Particularly if you can afford to stretch to the rorty C300.

The 4 Series line offers three distinct points of difference from the more traditional 3 Series, each with their own attraction. The sharpening of the sticker prices and the additional spec helps their cause as well, with the 430i Coupe probably our pick of the range. The 440i is the firecracker of the group, while the 420d is also worth a look, thanks to its value and prodigious torque output.

If you're checking out the new C-Class for the first time from the front, you'll probably think… hmm, it looks just like the old one, and that's largely true.

But a side view reveals proportions that have changed significantly, thanks to the more raked windscreen, shorter overhangs and cleaner lines, which give it a slightly smaller S-Class look.

Which is more in fitting with where Mercedes wants to place this car against its 3 Series and A4 competitors.

Additionally, the taillights are split for the first time, allowing for a wider boot aperture since the lid now contains some of the lighting elements.

The shrunken limo looks aren't just the whim of some designer or Mercedes-Benz marketing department copywriter, either.

Underneath is an albeit highly modified version of the latest S-Class' MRA2 platform, which results in the longest (at 4755mm) and widest (at 1820mm) C-Class in the series' 40-year existence, as well as the first with this level of electrification capability.

Height and wheelbase dimensions also see a stretch, by 8mm and 25mm to 1450mm and 2865mm over the previous model respectively, and to the benefit of passenger accommodation.

Speaking of which, get used to this new interior aesthetic and general layout – it's a look that's probably going to filter through to most coming non-EQ-branded Mercedes models over the next few years.

From S to C to future E and A classes and beyond. It's a rare instance of trickle-down economics actually working!

No external changes to the 4 Series' bodywork have been affected  for  this midlife refresh, but there have been plenty of tweaks to the standard equipment offerings right across the board.

One of the best things about the new C-Class is that it's larger and therefore roomier than before. It's also higher quality, easier to use, more comfortable to sit in and - overall - more of a delight to behold.

In contrast, the old C-Class dash looked and felt like it was designed for a much cheaper car, especially compared to Audi's efforts.

Obviously related to the S-Class this time around, it's clear Tesla provided the inspiration for the twin floating screen look and layout, which are just right in their driver orientation and ease of functionality.

There's never really been anything wrong with Mercedes' old front seats, but these AMG Line items are both sumptuous and bracing, keeping their occupants well located ahead of the clever and thoughtfully laid out dashboard.

The brilliantly high-resolution MBUX multimedia and voice-recognition system now works as it should - intuitively and logically, with the screen menus simple to recognise and easy to use, and most without the need to get lost in confusing sub-menus. Just like BMW has managed for years.

If you want to change the instrumentation design, it's now a couple of clearly marked steps, using handily placed switchgear. The same goes for the superb climate control and audio systems. And the wireless Apple CarPlay/Android Auto connected faultlessly and worked a treat. Effortless see-and-push operation all round, backed by concise and classy graphics.

No more degree in Earth-to-Mercedes comm skills required to master this C-Class interior.

Yet there's just enough old-school Benz features to appeal to brand diehards, from the eternal door-card mounted electric seat controls and column-mounted gear shifter, to the deep centre console and turbine face-level air vents. They meld together beautifully with the advanced tech also on offer, like the optional augmented-reality head-up display with 3D-graphics.

Annoyingly, on one of our test cars, that tradition also extended to a couple of squeaks and rattles, proving that maybe Mercedes hasn't quite conquered all its past quality gremlins. And, like most luxury cars nowadays, endless ambient lighting choices are available of dubious taste.

Never mind. This is the finest C-Class front-seat environment since, well, probably the original W210 190E's of the 1980s.

And all those extra dimensions pay dividends in terms of interior space in the back seat.

There's plenty of knee room even with the tester sat behind their 178cm frame; head room is adequate even with the optional sunroof fitted, and there's ample shoulder space. So, it's more comfortable than any C-Class ever has been in terms of sheer dimensions.

Additionally, the rear backrest is well angled, while the cushion is deep enough to provide sufficient thigh support. But the centre perch is a bit of a squeeze for all concerned. Best avoided.

There's also added practicality to be found with the large and deep door pockets, front seat-back map pockets and folding centre armrest, that not only has a tablet holder, but when pressed in twice, also reveals sliding cupholders as well. Clever.

The C-Class rear seat is really lacking for nothing, with face-level air vents, overhead lighting, grab handles and coat hooks all highlighting the level of thought that went into making this a practical compact family sedan.

Plus, the C-Class comes with this folding ski port, which along with the folding rear seats, increases boot volume from 455L to, well, a lot more. While that's not quite as good as others like the BMW 3 Series, it's big enough for this car.

Note that there is no spare wheel, as the tyres are of the limited-distance runflat variety.

Two-doors are never the most practical devices, but the 4 Series Coupe and Convertible duo make a decent fist of it for front-seat passengers. There are bottle holders in both doors and a pair of cupholders in the centre console, along with a large lockable glovebox.

The centre bin is, however, quite shallow, and houses the car's single USB port inside it. There is covered storage under the dash for smaller items, and a small rubber-lined tray that the current crop of phones has outgrown.

The rear seating in the Coupe is reduced to almost a formality, especially if the front seat passengers are tall and the front seats are set back, while the sloping roofline reduces head space quite considerably. A centre armrest contains a pair of cupholders, and there are small side pockets.

Rainy conditions precluded us from trying the Convertible's metal folding roof, but the rear seat space restrictions also apply here. Its 370 litres of boot space is roomy enough for a drop-top, while a clever lifting function raises the folding roof structure up by about 300mm to allow luggage to be stowed under the panels when the roof is down. Capacity drops, though, to just 230 litres.

The Gran Coupe, on the other hand, is the most practical car in the entire 3 and 4 Series line-up outside of the 3 Series Touring wagon. With a large, flat load area, and a hatch-like tailgate, the Gran Coupe can swallow 480 litres of gear with the seats up and an impressive 1300 litres with the seats lowered.

Face-level rear vents, more head and backseat legroom – not to mention the fact you don't have to squeeze into the rear past the front seat – makes the Gran Coupe a most useful device, and it's little wonder it's the most popular variant of the three.

Entry into the 4 Series world now stands at $68,900 plus on-roads for the petrol 420i Coupe and Gran Coupe, and tops out at almost $118,000 for the 440i Convertible.

Both the 420i and 420d have been boosted by the addition of adaptive M dampers, a heads-up display, powered folding rear-view mirrors, lane-change warning, driving assistant and BMW's surround view camera with top and side views.

BMW claims the extra kit is worth just over $8000. Leather seats, sat nav, BMW's ConnectedDrive Emergency call system, bi-Xenon headlights and reversing camera are also featured. An eight-speed automatic transmission is offered as stock, but a six-speed manual can be optioned at no cost.

The diesel version costs an additional $2200 over the petrol powerplant.

Stepping into the 430i, the M Sport Package is offered as standard, with the Luxury line, which includes a leather-trimmed dash, a no-cost option.

Additional standard equipment over the outgoing 428i includes 19-inch M rims, heads-up display, lane change warning, driving assistant and surround view camera. The 430i also gains electric lumbar support for driver and front passenger seats and a nine-speaker stereo system over the base 420i.

Finally, the range-topping 440i scores a heads-up display, lane change warning, driving assistant, surround view camera, adaptive LED headlights, leather dash, front seat heating, high beam assist, active cruise control with stop and go function and parking assistant over the outgoing 435i.

Over the 430i, the 440i also gets variable sport steering, a Harman/Kardon surround sound system with 16 speakers, a leather instrument panel (with M Sport Package), ConnectedDrive internet and concierge service, and air collar neck-warming ducts for the 440i Convertible.

Probably the biggest departure compared to any previous C-Class is this generation's switch to direct-injection four-cylinder-only powertrains – including the coming Mercedes-AMG high-performance versions. Now that should be interesting.

As mentioned earlier, the C200's four-cylinder turbo engine is now about 25 per cent smaller in capacity, down from 2.0L to a 1496cc 1.5L twin-cam 16-valve turbo engine. Dubbed the M254, it pumps out 150kW of power at a high 6100rpm and 300Nm of torque between 1800-4000rpm.

That's not to say it's lacking in muscle, though, since it can sprint from zero to 100km/h in 7.3 seconds, on the way to a 245km/h top speed. These outputs are at least a match for the bigger-engined 3 Series and A4 equivalents, by the way.

If it's more you want, then the C300 features a 1999cc 2.0L turbo version of the M254, delivering 190kW at 5800rpm and 400Nm between 2000-3200rpm. This slashes that 0-100km/h time to a speedy six seconds flat. There's also an extra 20kW of overboost available for short periods if you're really in a hurry, while - where legal - it's possible to hit 250km/h.

Both send drive to the rear wheels via a nine-speed torque-converter automatic transmission, while the 48V mild-hybrid system, dubbed EQ Boost, employs an integrated starter-generator and lithium-ion battery that provides an additional 15kW and 200Nm of electric boost at low engine speeds.

So, while it doesn't ever run purely on electricity, the electrification tech certainly either brings more punch or takes the load off the petrol engine, depending on how you're driving it.

There are two new petrol engines, two new badges and prices cuts of up to $10,000 right across the board for the line-up, along with additional standard equipment that improves the value equation even further.

The line kicks off with the 420, which can be had in either diesel or petrol guise. The 420i gains BMW's new B48 2.0-litre four-cylinder turbo petrol engine, which gains 5kW over the old motor to produce 135kW and 270Nm.

It also benefits from slightly improved fuel economy, with a drop of 0.3 litres per 100km for the Coupe and 0.5 for the Gran Coupe to 5.8L/100km, and a fall of 0.2L for the Convertible to 6.2L/100km.

The 420d retains its 140kW, 400Nm 2.0-litre four-cylinder turbo diesel engine, which returns 4.3L/100km in the fixed roof cars and 4.7L/100km for the Convertible.

The 430i – formerly known as the 428i – also receives the new 2.0-litre petrol engine, albeit in a 185kW/350Nm tune. Its fuel economy drops a healthy 0.6L for the Coupe and Gran Coupe and 0.4L for the Convertible, posting figures of 5.8 and 6.3L/100km respectively.

The top-spec 435i has been transformed into the 440i with the addition of BMW's new Twinpower 3.0-litre straight six petrol motor. Its output jumps 15kW to 240kW and by 50Nm to 450Nm, and its consumption falls by more than half a litre to 6.8 litres per 100km for the closed-roof pair and 7.2L/100km for the Convertible.

All cars come standard with a 'traditional' ZF eight-speed torque converter automatic transmission with steering wheel paddles as standard fitment, while a six-speed manual gearbox is a no-cost option across the line.

Remember when I said that the C-Class moved to an all-four-cylinder engine range? Well, that's primarily to help it better meet fuel consumption, efficiency and lower emission targets.

On the Australian combined fuel consumption cycle, the C200 manages 6.9 litres per 100km – and that's extremely impressive for a medium-sized sedan weighing almost 1.8 tonnes. So is the fact that the larger-engined C300 returns only 0.4L/100km more at 7.3L/100km. Fitted with a 66-litre tank, these numbers suggest that the former can average nearly 960km between refills while the latter can manage just over 900km.

These figures translate to averages of 157 and 164 grams per kilometre of carbon dioxide emissions respectively. On the flipside, both these Euro-6 emissions rated engines require 98 RON premium unleaded petrol to deliver their best.

So much for lab tests. Out in the real world, we drove both cars for several hundred kilometres on a hot summer's day, from inner Melbourne during peak-hour traffic, to some great curvy rounds out in central Victoria, featuring some tight corners and ample opportunity to really stretch both cars' legs.

Over these routes, we averaged an indicated 8.4L/100km in the C200 and – astonishingly – 7.4L/100km in the C300. Yes, the larger and more powerful engine proved more economical.

Clearly, along with the advanced aerodynamics, engine stop/start system and 48V mild-hybrid tech, all that downsizing works. No wonder Mercedes deemed it unnecessary to bother with diesel engines for this generation C-Class.

Our brief test loop on a rainy, blustery Melbourne winter's day in all three model types (but no diesel) netted varying fuel consumption readings across the line; we recorded 8.4L/100km in a 420i sedan against a claimed figure of 5.8, 9.8L/100km for the 430i Gran Coupe against a claimed figure of 5.8L/100km, and 8.4L/100km against the 440i Gran Coupe's 6.8L/100km.

There has been a philosophical shift in how the C-Class is presented.

Even with their standard-in-Australia AMG Line package, the regular grades like the C200 and C300 are now leaning into the brand's luxury heritage, while the BMW-baiting sports sedan versions will be left to the coming AMG versions.

And this in turn profoundly informs how the W206 drives.

Even with the optional Sports Pack on 19-inch wheels, the C200 as tested finally feels like a premium midsized sedan experience. Muted at start up, the 150kW/300Nm 1.5L turbo steps off the line smartly and smoothly, its nine-speed auto shifting effortlessly through the gears to keep the engine feeling lively and lusty.

Around town it's easy to mistake the engine as a larger-capacity unit, since throttle response is instantaneous, with little to no lag detectable. It's a strong start for a base powertrain, especially as the C200 settles into a relaxed cruise at freeway speeds. Cycling through the driving settings also reveals how feisty the 'Sport' mode is.

But the 1.5L's lack of size becomes obvious the moment you need to overtake quickly, or when a quick squirt of acceleration up a hill is required, because the engine needs plenty of revs to approach that 6100rpm power peak. While still pretty brisk in these situations, it's also fairly vocal too, with a sense of having to work hard to maintain momentum.

Switching to the C300 highlights how much better suited the 190kW/400Nm 2.0L turbo is to highway driving, leaping forward with much more force and conviction, across the entire performance spectrum. In every metric, this is a better choice – throttle response, mechanical refinement, cruising ease. And the fact that the onboard computer showed less fuel consumption cements our preference for the larger-hearted C-Class.

In fact, both models possess a chassis that feels like it could do with a whole lot more power. Light and tight around town, the steering weighs up nicely at higher speeds, with a linear and reassuringly planted feel. The same also applies to how confident and controlled the Mercedes feels through fast, tight turns, yet settles into a relaxed and comfortable tourer along long, straight stretches of road.

It's a pity, then, that such dynamic agility and prowess doesn't really involve the driver, since the steering feels quite isolated from what's going on underneath; for the vast majority of C-Class buyers, that's fine. But, as a quick spin in any latest BMW 3 Series or Jaguar XE will reveal, there isn't an intimate, two-way connection going on here. That's probably going to be reserved for the AMG models.

Our C200 rode on bigger wheels and steel springs, while the C300 was fitted with optional adaptive dampers. In the previous-generation C-Class, the differences would be stark: a busy and jittery ride in the former, compared to soft yet still unsettled suspension in the latter.

That's all ancient history now, as even the 'passively' suspended C200 now isolates its occupants from the rough and tumble of our inconsistent roads. Still firmish, but no longer harsh.

And the C300 with adaptive dampers seems downright plush by comparison, while offering the driver personalisation options within the aforementioned driving models to tailor the steering, performance and engine sound settings that best suit the prevailing mood.

Too bad there's some road and tyre noise intrusion heard inside when driving over coarse bitumen roads. This is a common pitfall amongst German vehicles in Australia.

Still, it doesn't detract from the fact that the whole chassis set-up can at-last cushion and cosset occupants like, well, a mini S-Class.

Which is the whole point of the W206 C-Class. It now majors on comfort and reassurance like the better Mercedes-Benz models used to, while still being suave and sprightly enough to be a memorable – if not over-exciting – drive.

As a result, the C300 especially is a much-more likeable car than past iterations. Just remember to tick the adaptive damper option for the most optimal experience. Job well done, Mercedes.

BMW introduced a raft of tweaks to the 3 Series platform late last year, which have translated over to the 4 Series. The key addition across the line is BMW's two-stage adaptive dampers that feature a Sport and a Comfort circuit, fitted as part of the M Sport pack that comes standard on the 430 and 440, and is a $2600 option on the 420.

Larger 19-inch rims are fitted to the 430i and 440i cars, while the 420 gets 18s out of the box. It's possible to fit 18s on the more expensive cars, as part of the no-cost Luxury option pack that supplants the standard M Sport pack.

While our test was brief and held in less than ideal road conditions, the large-wheeled 4 Series really didn't enamour themselves to this author. There's a distinct lack of communication from the tyres and chassis through the steering wheel and your backside, while the combination of firm Sport shocks and large 19-inch wheels with narrow-section tyres made for an uncomfortable ride over country roads.

Sampling a 420i with the Luxury 18-inch rims, however, improved things immensely, with much better feedback and comfort that didn't come at the expense of handling.

One of BMW's strong points should be its steering, given all the 3 and 4 Series cars are still rear-wheel-drive… but it's not, unfortunately. The electrically assisted set up is far from perfectly calibrated, feeling too dull and digital underhand, no matter what the setting.

The pick of the bunch performance wise is – logically – the six-cylinder 440i. The turbo powerplant is potent from right down the rev range, with a muted yet still pleasing engine note permeating the cabin. The self-shifting mode on the eight-speed auto does a good job of keeping up as well.

The updated 2.0-litre four is a sprightly performer, too.

 six airbags, lane departure warning, pre-collision safety pack, parking sensors, active cruise control with collision warning, AEB and pedestrian warning, along with reversing camera and surround-view cameras across the line.

Kudos to Mercedes-Benz for being the first luxury manufacturer in Australia to offer a five-year/unlimited kilometre warranty – matching most other mainstream makers. Lexus and Audi have only recently followed suit.

A five-year roadside assistance subscription is also included. Service intervals are 12-monthly or at every 25,000km, whichever occur first.

Additionally, a four-year capped price service plan is available, at $550 for the first year, $900 for the second, $1000 for the third and $2450 for the fourth, totalling $4900.

Alternatively, buyers can also choose three pre-purchase service plans to save a bit of money, but these must be bought prior to the first service.

BMW offers a Service Inclusive program at the time of purchase, which for $1340 covers everything – including items like spark plugs, brake fluids and other fluids - for five years or 80,000 km scheduled. The cars are also covered by a three-year free roadside servicing program, in addition to BMW's two year, unlimited kilometre warranty.