Mercedes CLS review

It was always accepted that if you wanted a good-looking coupé, you had to live with compromises – until the first Mercedes CLS rocked up with a svelte side profile but four doors. 

The CLS proved to be a hit because it was as unique as a newly discovered galaxy. No manufacturer had thought of combining four-door versatility with the rakish front and rear-end looks of a two-door coupé – and, boy, did it go down a storm.

Fast-forward to today and we’re on the third generation CLS, but it's no longer ploughing a lonely furrow. As with all great ideas, the design has been scrupulously studied and brazenly plagiarised by all and sundry.

Now the market includes the Audi A7 Sportback, BMW's 6 Series Gran Turismo and 8 Series Gran Coupe plus the VW Arteon. The concept of chopping the roof height of something less exciting has also spread to the SUV world, with coupé SUVs such as the Audi Q8, BMW X6 and Mercedes' GLC coupé and GLE coupé.

That’s good for you, though, because it means more options. So which is best? Read on and this Mercedes CLS review will tell you all you need to know about the latest model, including how it compares with those rivals.

We'll also take you through what it's like to drive, whether there's enough space for passengers, how much it will cost to run, which trim and engine we'd recommend, and much more.

When you’ve finished researching and are ready to buy a new vehicle of any make and model, make sure you head over to the free What Car? New Car Buying section to find the best price and check out some great Mercedes CLS deals.

If you’re looking for a petrol car, you’ll either need to spring for the high-performance Mercedes AMG 53 or look at either an Audi A7 Sportback or BMW 8 Series Gran Coupe, because both those rivals have greater engine options. 

The AMG 53 uses a 3.0-litre straight-six engine with some clever hybrid tech to boost efficiency a little, but we’re sure you’ll be more interested in the 429bhp this engine delivers and the 0-62mph time of 4.5sec. Needless to say, it's not an engine short of overtaking urgency, although some may find it rather muted for a sportier offering. It's louder in its sportiest mode, but the sounds are digitally enhanced and rather contrived.

As for diesels, the range starts with the 300d, featuring a 2.0-litre four-cylinder engine with 261bhp. It’s refined at a cruise and has as much pulling power as anyone would ever need, but can be a touch grumbly under acceleration. It’s not quite the full-fat 335bhp 400d 4Matic, but it’s a tidy sum cheaper and a bit more frugal. All things considered, it’s our pick of the range.

The 400d is a belter for those willing to splash the cash. It's super-smooth most of the time – certainly more so than the equivalent diesels in the A7 and 8 Series Gran Coupe – and there’s effortless pace available with just a tickle of the accelerator. When you gun it, it takes on a slightly harder-edged growl while the pace turns ballistic.

The standard nine-speed automatic gearbox used on all the above is decidedly slick and responsive, but not everything else is quite so cultured. While the CLS is whisper-quiet and more hushed than its rivals on the motorway when it comes to wind noise, road and suspension noise (with the standard passive suspension) are noticeably worse.

That standard passive suspension also makes the ride in town rather lumpy over ruts and ridges compared with a 6 Series GT – even on the smallest (19in) wheels available. It does settle down nicely on the motorway, but not to the same extent as a smooth-riding A7 Sportback fitted with optional air suspension.

You can fit adaptive air suspension to the CLS (standard on the AMG 53 Edition 1 trim) as well, but unfortunately it's a let-down. In the softest Comfort mode, it soothes out bumps around town up to a point, but when you strike a large, sharp-edged obstacle with any pace, the suspension produces a thwack so loud you might think you've damaged something.

It does get better at speed, feeling quite wafty on the motorway. That suppleness disappears if you press the Sport button with a little more fidget over rippled roads, but the positive is better control over crests and dips.

What is commendable is the way the CLS handles. Okay, it’s not as pin-sharp or finessed as the more expensive Porsche Panamera – which would be the keen driver's choice here – but it feels similarly sure-footed to an A7 Sportback along a twisting back road.

The steering is precise and predictable, the brakes smooth and dependable and, with the four-wheel drive of the various 4Matic models, it’s tractable, even in slippery conditions.

Even compared with the Audi A7 Sportback and BMW 8 Series Gran Coupe – let alone regular luxury saloon cars – the driving position in the Mercedes CLS feels cocooning, low and sporty. In terms of adjustment for the steering wheel and figure-hugging seats, there’s enough to accommodate most shapes and sizes.

The only issue is the bulge in the transmission tunnel by your left leg that results in offset pedals and a slightly skewed seating position (especially because the steering wheel is shifted slightly over to the left). It’s far from uncomfortable, though.

The driver’s seat comes with full-electric adjustment as standard, and includes three position memory and adjustable lumbar support (although the controls are buried in a menu in the central touchscreen).

Seeing out of the front is fine, but visibility is tricky out of the back due to the tapering rear end that makes the windows shallower. However, Mercedes has thought about the stress of parking and added front and rear parking sensors, as well as a rear-view camera, as standard. At night, the standard adaptive LED headlights are superb, too.

There’s little doubt that the CLS has one of the snazziest interiors in the class, with a rich mix of materials including stained wood veneers and chrome highlights. It looks even plusher when bathed in the ambient lighting at night. Full leather seats are standard and you can upgrade to baby-soft nappa leather for an added charge (if you opt for the AMG 53, you get nappa leather as standard).

While all that looks great, it has to be said that, compared with the best-finished cars in the class, of which the A7 would be one, the feel of some parts of the interior feels a bit below par for the price.

In terms of infotainment, as you’d expect, sat-nav, a DAB radio and Bluetooth are all included, as well as two 12.3in screens – one for infotainment and one directly in front of the driver in place of analogue instruments. All engine variants get an extra indicator in the driver’s display to show what the ‘EQ boost’ battery is doing – either assisting with small bursts of power or charging.

The infotainment system is controlled either from the touchpad on the centre console, via touch-sensitive buttons on the steering wheel, or through certain voice commands. If you don’t fancy using the car’s built-in MBUX operating system, you can always connect your phone to it with standard Android Auto and Apple CarPlay smartphone mirroring.

We approve of the CLS's physical touchpad controller because it’s vastly less distracting to use while driving than the touchscreen system in the A7. However, we still prefer BMW’s iDrive as found in the 8 Series Gran Coupe, because not only does it have easily accessible shortcut keys surrounding a rotary controller, but the menu layout and general functionality of the software is more intuitive in use.

Happily, you do get a top-notch Burmester surround-sound stereo with 13 speakers and 590W thrown in for free – which is certainly good enough to please most audiophiles.

Despite its sporty and intimate feel inside, leg room in the front of the Mercedes CLS is fine for six-footers, although head room is a little tight. That said, so far we’ve only tried cars with a sunroof fitted and, similarly equipped, the Audi A7 Sportback and BMW 8 Series Gran Coupe are no better.

Compared with a two-door coupé, the extra doors make life much easier for anyone getting in and out of the rear. Once inside, leg room is fine, although nowhere near as good as that in the 6 Series, while the difference in head room is marginal for anyone tall. You will struggle to get three abreast at the back, unless all of them are kids.

The saloon-style bootlid leaves a narrow aperture compared with the A7’s wide-opening tailgate, so the CLS won’t fit very bulky items. There’s still a good amount of space otherwise, because we managed to fit seven carry-on suitcases inside. There’s also some additional underfloor storage, with a collapsible basket you can unfold and use as a storage container.

If you need more room, 40/20/40 split-folding rear seats come as standard, allowing you to fit longer items when required.

The Mercedes CLS is not a cheap purchase – unless perhaps you’re a sheikh with an oily pond in your back garden – but it’s comparable to its rivals on list price.

That said, at the time of writing, PCP finance deals and leasing costs are sky-high relative to an equivalent Audi A7 Sportback and BMW 8 Series Gran Coupe. That's because depreciation plays a part in the finance calculations, and unfortunately the CLS has worse residual values than its two main rivals after three years. 

Combined fuel consumption is reasonable, too. Even the more powerful 400d is rated to return 42.1mpg, although CO2 emissions of 175g/km put it squarely at the top of the company car tax bands. If you want something with a low benefit-in-kind (BIK) rate, you’ll have to look at an A7, because that can be had as a plug-in hybrid with reduced CO2 emissions.

There’s only one trim – AMG Line Night Edition Premium Plus – and it comes well equipped. As mentioned earlier, you get full-electric leather seats (which are heated in the front), along with three-zone climate control, 20in alloy wheels, digital instruments, front and rear parking sensors with a 360-degree camera system, LED headlights and power-folding door mirrors. Music lovers will also appreciate the excellent 13-speaker Burmester surround-sound system.

So far, there’s no Euro NCAP crash rating for the CLS, but the E-Class, from which it borrows heavily, is a five-star car. The CLS comes with automatic emergency braking (AEB), traffic sign recognition and lane assist as standard, but blind-spot monitoring is reserved for the optional Driving Assistance Plus package.

The CLS didn’t feature in our 2020 What Car? Reliability survey, but Mercedes as a brand was in the bottom third of the manufacturer’s list in 26th place out of 31, well below the likes of BMW, and four places behind Audi.

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