Having driven the Mercedes-Benz S 500 Cabriolet and absolutely adored its bias towards supreme comfort, does sporting things up for the Mercedes-AMG S 63 Cabriolet ruin this cultured proposition? Well, the ride goes from 10 out of 10 to 9.999 out of 10, perhaps, but by way of compensation you get that brutally effective 5.5-litre V8 engine and a soundtrack to die for...
In the metal
AMG's styling on these cabriolets and roadsters is reserved compared to some of Affalterbach's historic products, or even existing cars like any iteration of the C 63, which gets wider arches to cope with its increased track. No such metalwork is required on the S-Class Cabriolet, however, and as the only non-AMG model (the S 500) comes with AMG-inspired body styling, it'll take you a few moments to register the changes for the S 63. The A-wing front lower bumper is a slightly different and more aggressive shape here than it is on the S 500, while in the 63's grille you'll spot two bars flowing away either side of the three-pointed star, instead of just one. The S 63's re-sculpted lower side skirts feature an aluminium trim and round the back are the trademark quad exhausts separated by a black diffuser with vanes, while at the outer edge of the rear bumper are extra air vents to improve airflow. Other than a larger set of 19-inch wheels in the arches, though, the S 63 looks a lot like the S 500.
Which is fine, because the S-Class Cabriolet is a beautiful, elegant and suitably expensive-looking thing. And so is that exquisite interior, again not ruined by a few AMG details - such as the flat-bottomed, chunky steering wheel, the brand's logo embossed onto the top of that clever centre armrest lid that is hinged on both sides, a pair of sports seats and some carbon fibre trim scattered about the place. Choosing an S 63 over an S 500 brings in, aside from the AMG power and styling additions, a Driving Assistance Package, upgraded Nappa leather and a 13-speaker Burmester sound system guaranteed to take your head off at full volume; tasty.
You have to consider the S-Class Cabriolet's dynamics in the wider context of Mercedes' current fleet, and what cars could possibly be on the way. Up at the rarefied atmosphere of its most glamorous models (Mercedes is calling 2016 its 'Dream Cars Offensive', so that should give you some idea of the choice on offer for plutocrats), Stuttgart already has two open-top lines - this Cabriolet and the evergreen SL - and then the potential to turn the AMG GT supercar into a convertible; it happened its SLS predecessor, after all. On a sliding scale from 'sporty' to 'comfy', then, you'd say it would run soft-top GT, then SL, then this S-Class Cabriolet.
To that end, you'd expect the S 63 Cabriolet to therefore be quietly competent in the bends, if not quite as entertaining as its existing SL 63 stablemate. Not a bit of it. A hefty and big car - it's 2,170kg and 5,044mm long - the S 63 does that classic trick of shrinking around its driver. Absolutely fantastic AMG steering, which is a little sharper and more feelsome than the speed-sensitive electric power steering rack on the S 500, makes getting the S 63 to turn into a corner precisely where and when you want it to an absolute breeze. It will rip round curves at faintly silly speeds with next to no body roll, and then its epic seven-speed transmission fires you out onto the following straight in precisely the right gear to ensure thunderous acceleration. It might not be a light and nimble machine, but the S 63 Cabriolet is remarkably effective on sinuous roads.
It manages to be so entertaining to hoon about in without sacrificing the extremely civilised cruising manners of the regular Cabriolet. Sure, the AMG-tweaked Airmatic suspension and adaptive dampers have - for want of a better word - firmer settings than those on the S 500, but they do not spoil a ride that is still better than practically any other car that's on sale today. Without body control ever becoming loose, the S 63 feels like it is floating over tarmac, rather than rolling on it. And like the S 500, the AMG has all the same tricks to keep its occupants as comfortable as possible - such as Airscarf, Aircap, double-glazed windows, great aerodynamics and a massive amount of sound deadening.
Do you want us to talk about the noise? What do you think it sounds like? It's an AMG 5.5-litre V8 breathing through a naughty exhaust in a car in which you can open the roof to better hear its song. Whether burbling about town in Comfort mode or bellowing up a mountainside in Sport+, you'd pay the huge asking price for this Cabriolet for its soundtrack alone. There simply aren't enough glowing superlatives to describe the sonic treats the S 63 serves up.
Confession time here, though, because one of those foibles of market-dependent spec means the left-hand drive S 63 we drove was fitted with 4Matic all-wheel drive, as all left-hand drive 63s will be; however, in right-hand drive markets, power and torque will only be going to the rear axle on the S 63, as with every example of the S 500 and S 65. We'll use that closely-related SL 63 (also rear-wheel drive only) as a yardstick again to say that we're confident the lack of drive to the front axle won't turn the S 63 Cabriolet into a dynamic mess.
What you get for your money
More kit, more road-holding prowess and more naughty noises are to be had stepping up from S 500 to S 63, but as their performance stats are pretty close, the S 500 is a bit better on fuel and it's around €75,000 cheaper, you have to ask yourself how often you'd be able to tap into the S 63's extra dynamic ability. If such occasions are of the same frequency as blue moons, you'd be better off sticking with the 500 - especially as its ride is ever-so-marginally better. Us? If we had such large amounts of cash, we'd demand that AMG music...
Bentley Continental GTC: the GTC has been around since 2006 and the shape hasn't changed much in that time, although the Conti is a similarly classy all-round experience as the Merc.
Mercedes-AMG SL 63: we've got to list it - same drivetrain, fewer seats and a metal roof. In other markets, the SL 63 can be around €40k cheaper than the S 63... tempting.
Rolls-Royce Dawn: sublime as the S 63 is, for some, Rolls-Royce will always be a cut above. The Dawn is frighteningly brilliant and fearsomely expensive.
The Mercedes S-Class Coupé and Cabriolet models are not supposed to be out-and-out sports cars, as good a showing as the S 63 Cabriolet puts on in this department, so for maximum posing power and the ultimate feel-good factor, you're going to be better off picking the soft-top over the Coupé - despite the price increases. Go for this Mercedes-AMG machine and what you end up with is a car that is as near as dammit master of all trades and jack of none. The S 63 Cabriolet is a genuine automotive superstar.