Performance & drive
What it’s like to drive, and how quiet it is
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.
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.