The original CLS had the segment pretty much to itself, with Merc managing to flog 170,000 of them in six years. But things will not be so easy for the new CLS, which steps into a class now occupied by such varied competition as the Audi A5 Sportback, a sleekified Jaguar range (both XF and XJ), the soon-to-be-launched Audi A7, the BMW concept granturismo thingy and, at the top end, the Porsche Panamera.
The nose now apes the thrusting grille of the SLS supercar, the side profile has sprouted some new crease lines and a muscular haunch over the rear wheel, and the rear lights have gone all sparkly and LED. The front lights are also now full LED jobs, a world first for Merc that uses a total of 71 LEDs to create a distinctive and effective set of lamps.
Inside, the wraparound cosiness that so distinguished the previous car has been diminished a little in favour of a more conventionally Mercedes interior. It's still much warmer than, say, the cabin of an E-class or C-class, but some of the unique character of the original has disappeared.
Underneath the bonnet there will eventually be a choice of four engines, two diesel and two petrol. The 262bhp, 455lb ft 350 CDI will be available from launch, as will the 302bhp petrol-powered 350 CGI. The 201bhp 250CDI (the first four-cylinder engine to feature in a CLS) will join the ranks a few months after the rest go on sale in March 2011, but the key engine (at least from a PH perspective) is the all-new motor in the range-topping CLS 500.
This is because it drops the fine but venerable 5461cc naturally aspirated V8 in favour of an all-new 4.6-litre V8 with twin turbos. In the process, it jumps from 382bhp to 402bhp, and from 391lb ft of torque to a seriously healthy 442lb ft, all of which is available from just 1800rpm. It's all very impressive, and Mercedes even claims a provisional 31.3mpg from its combined-cycle run. (We didn't get anywhere near that, but this may have had more to do with the twisty Tuscan hill route of our test drive than any over-egging of fuel consumption puddings on the part of Mercedes.)
The only thing that let the drivetrain down on our test car was Mercedes' 7G-tronic S gearbox, which seemed often to hunt unnecessarily for ratios - and then provide you with the wrong one. It was also often reluctant to swap ratios when commanded to by a flick of the wheel-mounted paddle shift.
The chassis is based broadly on the E-class, but has wider tracks front and rear, and an entirely new front suspension system designed specifically to cope with the car's 19in alloys. Another difference is an all-new electric power steering set-up, which sounds ominous - these systems have traditionally delivered less impressive feel than hydraulic ones - but actually works quite well.
Mercedes' brave decision to set the launch up on the windy and tight mountain roads around the Futa pass - part of the Mille Miglia course - could be seen as a foolish one for a large executive saloon (sorry, coupe), but the CLS performs quite well.
True, it feels rather large for such roads, but the brakes remain unfazed even after a strenuous downhill workout, and the fact that it remains the same weight as its predecessor despite a growth in dimensions (aluminium doors that save 24kg are a big part of that) afford the CLS an agility consistent with the term 'coupe'.
Mercedes might not have the four-door coupe game to itself anymore, but the CLS is an enjoyable, accomplished car and deserves to be able to carve itself out a sizeable market among its various and varied rivals. Now all we need is the AMG version...