Rolling comfort and mechanical refinement are qualities that seem to be designed out of the new car market by the year, sacrificed for added safety, performance and dynamism.

The Mercedes S-Class waves the flag for those former qualities with spectacular fervour, however – just as it should in a segment where choosing to drive the car in question is an optional activity.

Diesel versions are badged 'Bluetec' instead of 'CDI', so most won't recognise a diesel S 350 from the outside

Everything this car does, from control input to resulting response, is engineered to happen quietly and with the minimum of intrusiveness to the company director reposing in the back seat.

Which is why the fact that what's likely to be the most popular model, the diesel S 350d, needs fully a second longer than an equivalent Jaguar XJ to hit 60mph matters not a jot. It trades outright pace for the ability to move away from a standstill with beautiful smoothness and to change gears imperceptibly even at wide throttle openings.

Convention says this should be the noisy diesel of the range, but the isolation of the car’s 282bhp 3.0-litre straight-six is absolutely staggering. With the doors thunked tight shut, the engine’s idle is just about audible from inside the cabin, but on the move – when operating at cruising revs – it really isn’t.

There is some road noise, and some more noticeable wind noise, but even so, we recorded 57dB of cabin noise at 50mph. That’s 4dB less than in a Bentley Flying Spur and 3dB less than in a Range Rover TDV8. That’s an advantage anyone would appreciate over already very refined cars.

Perhaps the S-Class deserves better than Mercedes’ current six-pot turbodiesel, which is underpowered compared with some in the class. Smothered by the car’s 2.2-tonne weight, the six-cylinder offers little in the way of urgency.

But whether you’re driving or in the back, chances are you won’t care – as long as it continues to operate so damned discreetly.

The more powerful 4.0-litre twin-turbocharged V8 S560 produces 462bhp and 516lb ft. It gathers speed in a smooth and refined fashion, but is capable of dispatching the 0-62mph sprint in just 4.6sec. This S-Class spears along with a wonderfully nonchalant manner that will make it hard to beat as a trans-continental express.

That said, it feels just at home on a steady cruise at motorway speeds. Long gearing and reasonably strong reserves of torque provide a superbly relaxed yet flexible quality that makes the S-Class as impressive from the driver’s seat as it is with your legs stretched out in the back.


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Starting the AMG derivatives is the S63. Its twin-turbo 4.0-litre V8 generates an almighty 603bhp and 663lb ft, allowing for 0-62mph in just 4.3sec. It's devastatingly rapid and, despite what you might expect, claimed to be capable of averaging 30mpg. With only the colossal 6.0-litre V12 S65 managing to overhaul the S63 to 62mph by 0.1sec while chugging petrol at a rate of 23mpg.

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