BMW M5 vs Mercedes-Benz CLA-Class

What's the difference?

The term bigger is better doesn't often apply to performance cars, but it fits the M5 Competition perfectly. Big inside, but small outside when it matters, BMW's new performance flagship might be expensive, but there's no shortage of bang for those bucks.

The new AMG C 43 may lack the drama and excitement we’ve come to expect from the German performance brand, but that doesn’t mean it’s a bad car. Yes, it could be more extroverted and the ride could be improved, but this is still a sharp-looking sports sedan with loads of punch.

This is a car that speaks to its times, with ever-stricter emissions regulations making it harder and harder for car companies to produce loud, wild and charismatic cars. So Mercedes-AMG has worked within those boundaries and come up with a car that retains at least some of those core elements that has made the brand so desirable over the years.

Note: CarsGuide attended this event as a guest of the manufacturer, with accommodation and meals provided.

Let’s start with the new stuff, shall we? The BMW M5 Competition gets a new colour ('Frozen Dark Silver'), as well as new 20-inch (and lightweight) alloy wheel designs, and the grille, aero-designed wing mirrors and boot lip are finished in high-gloss black. The quad exhaust pipes are a black, too, as is the rear diffuser. Elsewhere outside, though, it’s the more muscular 5 Series of old.

Parked next to the much smaller M2, you quickly realise just how much bulk the M5 is carrying. It stretches 4966mm in length and 1903mm in width, and it looks every centimetre of those dimensions in the metal.

Climb inside, and you’re greeted with the familiar BMW interior design, with a huge centre screen, digital driver’s binnacle and a spaceship-level number of buttons surrounding the shift lever. The M5 Competition also arrives with full leather (seats and dash) trim, with carbon-effect dash inserts and aluminium pedal and foot rest trims.

Is it the most adventurous design treatment, inside or out, that we’ve ever seen? Well, no. But it looks polished and premium outside, and feels plenty comfortable inside.

Mercedes has created something of a problem for itself with its decision to introduce AMG styling packages for the majority of its range, including the C-Class.

It means the C 43 has to walk a fine line between looking like a unique AMG model, rather than just a C300 with a bodykit and not out-doing the C63.

To that end it has AMG’s now familiar grille with vertical bars, the unique and complex-looking 20-inch alloy rims and a small lip spoiler on the boot. But otherwise it is surprisingly understated for an AMG, lacking the more obvious and muscular stance of previous AMG offerings.

Inside, there’s a similar theme, with the typical Mercedes-Benz luxury appointments but with a sportier, AMG twist. The steering wheel is chunky and comes with AMG branding, metallic shift paddles and a pair of rotary dials/buttons that allow you to alter the various drive modes and settings.

The one on the right allows you to switch between the pre-set Comfort, Sport, Sport+ and Individual modes, while the one on the left can scroll between the various individual aspects to tailor the settings to the conditions.

In typical modern fashion the design is tech-laden, with a digital display for the instrument panel (that can be switched between various graphics) and a large, tablet-style central multimedia touchscreen that controls the majority of the car’s non-driving functions.

As far as performance cars go, the M5 Competition is a rolling Swiss Army Knife. For one, it’s bloody massive, which pays considerable dividends for passengers. 

Up-front, the seats are far enough apart to ensure you’ll be rubbing shoulders with exactly nobody. The centre console Is super wide (all the better for fitting all those buttons), allowing for a sizeable centre storage bin, joined by two cupholders and a second storage bin in front of the shifter which is also home to your USB, power and 'aux-in' connections.

In the back, there’s business-class levels of leg and headroom, and you can even fit another whole adult in the centre seat if you’re so inclined. The pull-down seat divider is home to two extra cupholders, sitting in front of a thick armrest, and the rear air vents get their own temperature controls. There’s an ISOFIX attachment point in each window seat, too. Pop the capacious boot and you’ll find 530 litres of storage space.

The new C-Class has grown slightly in size compared to the model it replaces, most notably with a 26mm increase in the wheelbase which you can feel in the cabin.

The front seat space is good, with excellent adjustability for the power-adjustable seats and steering column. I had no trouble finding my ideal seating position which makes for a more enjoyable and uncompromised driving experience.

Rear space is a bit tighter (which is typical for this segment/size of vehicle), but thankfully the standard seats do have very deep sculpting in the backs which allow for more knee space and foot room.

However, at approximately 180cm (six-foot), I wouldn’t like to sit behind my seating position for long periods as my knees were touching the seat back, and headroom is compromised with the panoramic glass roof.

In terms of small item storage there’s a lidded console box in between the front seats as well as a pair of cupholders and a small tray where you can place your mobile phone.

It’s worth noting, though, that early examples of the C 43 in Australia do not have a wireless smartphone charging pad, with that reportedly being introduced from February production.

While that’s good news, it’s not really competitive in this day and age to offer a car costing six-figures without such technology.

There’s also only a single USB-C power outlet in the front, which is another disappointment, but there is a pair in the back.

Mercedes does win some points back for a respectable 455-litre boot, which has a nice wide load opening that will make packing luggage easier.

We’ll get to the major change under the bonnet shortly, but another significant alteration for this latest C 43 is the price.

It now starts at $134,900 (plus on-road costs), which pushes it well above its market rivals, the BMW M340i xDrive and Audi S4, which start at $104,900 and $106,200, respectively.

However, Mercedes has added more technology under the bonnet and loaded the C 43 up with standard equipment, including its '4Matic' all-wheel drive system, adaptive damping, rear-wheel steering and 20-inch alloy wheels.

In terms of creature comforts, the C 43 is well-appointed, with leather upholstery, a head-up display, augmented reality navigation, a panoramic sliding sunroof, and a Burmester 3D surround sound system.

There are two option packages for the C 43. The 'Digital Light Package' costs $2400 and adds Multibeam LED headlights with 'Ultra Range' highbeam, 'Adaptive Highbeam Assist Plus' as well as active light function and cornering light function.

The 'Performance Ergonomics Package' includes AMG Performance front seats, an AMG Performance steering wheel in Nappa leather and microfibre and the 'AMG Track Pace' system for an additional $5200.

Yes, our all-electric future feels inevitable. And yes, there’s much fun and performance to be had from battery-powered EVs. But you can’t help but hope that future is a Star Wars style far, far away when you get acquainted with the BMW M5 Competition’s monstrous twin-turbo V8.

It’s good for a wondrous 460kW (up 19kW on the regular M5) and 750Nm. Both of which are big numbers, which are fed to all four wheels via an eight-speed 'M Steptronic' automatic. Happily, you can, at the push of some buttons, make the M5 a rear-driver again. It’s slower, but damn if it ain’t much more fun.

As a result, the performance numbers need to be seen (or better yet; felt) to be believed. The near-two-tonne M5 Competition will blaze from 0-100km/h in 3.3secs, 0-200km/h in 10.8secs, and push on to a limited top speed of 250km/h (or 305km/h, provided you do some BMW driver training).

The biggest talking point about this new car is the engine, with AMG downsizing from the old C 43’s six-cylinder to a 2.0-litre four-cylinder turbocharged petrol engine.

But it’s not just any turbocharged four-pot, because it is fitted with technology that Mercedes claims has been inspired directly from its Formula One team.

While the F1 team engine facility is based in England, this engine was designed and developed by the Mercedes-AMG team at its Affalterbach headquarters, but the concept of the electric turbocharger reportedly comes from the engine that powered Lewis Hamilton to multiple world championships.

The electric exhaust gas turbocharger - to give it its official name - uses a small electric motor on the turbocharger shaft to spin up the blades without having to wait for any exhaust gases to pass through it first.

To power the electric turbo the C 43 is equipped with a mild-hybrid 48-volt electrical system.

Mercedes claims this means reduced lag and improved throttle response for a sportier driving experience. 

It also helps make this small engine produce big amounts of performance, with AMG extracting 300kW of power and 500Nm of torque from this 2.0-litre, which is more power than the previous six-cylinder C 43 managed.

The engine is paired to a nine-speed multi-clutch transmission, which isn’t a dual-clutch with a pair of clutches operating on every second gear ratio, but instead uses a “wet start-off clutch” for better take-offs and smoother shifting on the move (at least in theory).

Power is sent to the road via all four wheels thanks to Mercedes’ 4Matic all-wheel drive system.

Well, BMW tells us you’ll return 10.7-10.8 litres per hundred kilometres on the combined cycle. But we would suggest that’s unlikely, unless you have Miss Daisy lounging in the back seat. Drive it like you definitely will drive it, and you can expect to pay for that privilege at the pump. 

Emissions are a claimed 243-246g/km of CO2, and the M5 Competition’s 68-litre tank will demand a premium unleaded petrol.

Despite the smaller engine you can hardly call the C 43 miserly, with a claimed combined urban/highway cycle rating of 9.1-litres per 100km. That’s only a 0.2L/100km improvement over the old six-cylinder.

On test, which included a return trip from Sydney to Bathurst via motorways and some dynamic back road driving, we saw a return of 11.8L/100km on the car's onboard computer.

While hardly hybrid-worrying, it’s impressive to think that driven modestly, such a potent engine can return a single-digit fuel figure.

Things this large simply shouldn’t be this potent. Like John Goodman suddenly toppling Usain Bolt at the Olympics, the BMW M5 Competition is bulk-defyingly good at the fast stuff.

The secret is its ability to hide those sprawling dimensions on a race circuit or twisting road. BMW’s engineers have poured plenty of work into stiffening the chassis of the M5 Competition, from new anti-roll mounts to additional under-bonnet bracing, to make the brand’s biggest performance sedan feel more lithe and responsive when pushed. 

And while its size never vanishes completely - and you find yourself praying you don’t encounter oncoming traffic on skinnier roads - engaging the Competition’s sportiest settings unlocks a Copperfield-level vanishing act.

The engine helps too, of course, pushing the M5 along with staggering ease, even when you’re pottering at suburban speeds. But really flatten your foot and the big V8 will force you to reassess your knowledge of physics. It’s really very fast, the Competition, the power flowing uninterrupted to the tyres, the engine still very willing to deliver more oomph long after your courage has jumped ship. 

The steering, direct though it is, lacks some natural feel, but you are always left with the impression that the Competition is going to go where you point it.

More fun stuff? Well, you can switch the traction control to a half-off setting, allowing for some smoking, drifting heroics before it drags you back into line. BMW calls it M mode, and it’s designed to make a hero of even the most ham-fisted of pilots, myself included. The braver still can deactivate traction control all together which, combined with rear-wheel-drive mode, turns the M5 Competition into the biggest and possibly most expensive drift car of all time .

Away from the track, though, the Competition version of the M5 is almost as good as transforming into a comfortable everyday commuter as its less hairy siblings. The adaptive suspension can be softened, and the steering lightened, to make toppling traffic a doddle. 

The keen-eyed among you might well have noticed we’re yet to touch on any major downsides of the drive experience. And you'd be correct. 

Let’s start with the good news. The new Mercedes-AMG C 43 is a quick car. The engine may be small in size but the electric turbocharger does its thing and provides plenty of punch.

You can get a performance boost, too, thanks to the belt-driven starter generator, which acts as a mild hybrid and gives you a surge of 10kW for a brief period if you need a sudden burst of extra speed.

The chassis is well-sorted, too, at least from a dynamic point-of-view. The rear-wheel steering can provide up to 2.5 degrees of turning, which improves handling at speed and manoeuvrability when parking.

However, there are some less-impressive elements to the C 43, too. The obvious one is the drama, or rather the lack thereof.

As I said at the beginning, the C 43 has never been as wild or raucous as the V8-powered C 63, but when you buy an AMG there’s a rightful expectation that it will provide some thrills.

The C 43 simply doesn’t have that character about it. Yes, it’s fast, but it produces that speed with efficiency rather than excitement.

And it’s not an engine size problem, because even the 2.0-litre four-cylinder A 35 and CLA 35 offer more ‘wow factor’ than the C 43.

Yes, the engine makes noise under acceleration (and it can be altered between discreet and sporty) but even at its best it sounds muted and lacks the evocative tone of a V8 or six-cylinder engine. 

Another disappointment is the transmission calibration, with the gearbox awkwardly shifting out of first gear on multiple occasions during our test drive.

In the taller gears it felt smooth enough cruising along, but given its low speed shifts we’d like to spend more time in the urban environment before passing final judgement. 

The other notable element of the driving experience we struggled with was the ride quality. While fine on the smoother motorways, our test drive included time on some patchy country back roads and the C 43, even in the ‘Comfort’ suspension setting, was simply too firm.

Riding on low profile tyres, the adaptive dampers struggled to isolate the cabin from the imperfections in the road, leading to a fussy ride at times.

Overall the C 43 is a good car, but it feels like there are still some areas where Mercedes could improve it to make it really live up to the AMG badge.

The C43 gets a comprehensive list of safety equipment that leaves little out. Obviously there are the usual passive safety items, like 10 airbags, including dual-front combined pelvic/thorax airbags and a front centre bag that drops between the front seat passengers to minimise the chances of a head clash.

Also included as standard is autonomous emergency braking front and rear (covering speeds between 7.0-200km/h), adaptive cruise control with active stop/go, a 360-degree parking camera, 'Active Parking Assist', 'Active Lane Keeping Assist', 'Blind Spot Assist' and, of course, anti-lock brakes with 'Brake Assist' and 'Adaptive Brakes' with Hold function and electronic stability control.

Also included are dusk-sensing LED lights, rain-sensing wipers and run-flat tyres with tyre pressure warning.

The C43 also comes equipped with Mercedes’ 'Driving Assistance Package Plus', which adds even more safety gear. This includes 'Active Blind Spot Assist', 'Active Brake Assist with Cross-Traffic Function', 'Active Emergency Stop Assist', 'Active Lane Change Assist', 'Active Lane Keeping Assist', 'Active Steering Assist', and 'Active Stop-and-Go Assist'.

While the C43 hasn’t been specifically crash-tested, the latest C-Class was rated by ANCAP with a five-star score for all models except the upcoming C 63 S E Performance.

The ownership package is yet to be confirmed, the M5 Competition will be covered by BMW’s three-year/unlimited kilometre warranty. 

Service intervals are condition, rather than time or distance, based, so the car will tell you when servicing is required.

The C 43 is covered by Mercedes’ five-year, unlimited kilometre warranty, which has become the new standard for the luxury car market.

Service intervals for the car are at 12 months/25,000km, which is on par with industry standard.

Mercedes-Benz Australia will offer a service plan for the C 43, prices were yet to be confirmed at the time of publication but the company has indicated it will be similar to the C300. 

That means $550 for year one, $900 for year two, the third service costs $1000 and the fourth year service costs $2450 - for a total of $4900 for the first four years of ownership.