2016 Mercedes-Benz S500 Cabriolet review

Sumptuous S-Class Cabriolet sets out to be the most comfortable convertible in the world; we’re not about to argue the toss.

WHAT IS IT?
The first open, four-seat S-Class convertible from Mercedes-Benz since 1971 fills out the S-Class range to six different body styles. Cruising to Palm Beach or Portsea was never so effortless.

WHY WE’RE TESTING IT
The convertible Mercedes-Benz S-Class comes almost two years after the launch of the coupe, offers the same three-strong twin-turbo engine range: 335kW 4.7-litre V8 (S500), 430kW 5.5-litre V8 (AMG S63), and 463kW 6.0-litre V12 (AMG S65), at an estimated $522,000, the most expensive Mercedes-Benz on offer. All arrive in Australia in September priced around $30K above the equivalent coupe.

MAIN RIVALS
Bentley Continental GT V8 Convertible, Maserati GranCabrio, BMW M6 Convertible, Rolls-Royce Dawn

THE WHEELS VERDICT
Supremely comfortable and luxurious convertible brings coupe levels of refinement, yet is also able to take on the character of a genuine high performance GT car. One Percenters need look no further.

PLUS: unbelievable levels of refinement and comfort, performance, equipment, sheer opulence
MINUS: rear seat not as roomy as coupe, body float in comfort mode, smaller boot

THE WHEELS REVIEW
WHEN Mercedes-Benz unveiled the C217 S-Class Coupe in mid-2014 as a pillarless two-door we knew a cabriolet was certain to follow. Twenty months later, the folding roof range lands. If anything, it’s even better looking than the coupe, open or closed; a swooping, indulgent beauty whose styling hugely benefits from not having to package a bulky, folding metal roof. The Cabriolet shares its basic dimensions – the 2945mm wheelbase, 1899mm width and 5027mm length – with the Coupe, though at 1417mm, it’s 6mm taller. And heavier, the Mercedes-Benz S500 sending the scales to 2040kg, 85kg over the Coupe, though added use of lightweight materials means the incredibly stiff body-in-white’s mass is identical. Fifty kilos of the extra weight comes from the astonishing power-operated roof.

The roof – please don’t call it a ragtop – is an engineering marvel; five layers of fabric that lower interior sound levels to silently match the coupe cruising at 110k/h. The taut outer skin (available in four colours – black, blue, beige and red) is three fabric layers, each 1.5mm thick; then comes a 20mm deep Polyester padding and finally a new Polyester with foil that Mercedes says delivers an “airtight’ fit. The soft top opens and closes in 20 seconds at speeds up to 60km/h and can be opened or closed by the key from outside the car. To prove its durability, Mercedes ran each colour roof through 20,000 open/close cycles, sufficient when the average owner is expected to do so maybe 100 times a year.

It works. Top up at 110km/h, the S500 is virtually silent. No noise from the roof, quiet engine, just a rustle of noise from the tyres. Mercedes claim that it’s only from 140km/h plus that it starts to produce more noise than the Coupe. Lower the roof, activate the Aircap that’s standard in Australia, and a louvre above the top of the windscreen extends as a wind block rises behind the rear seats. At 120km/h cruising with the side glass up, the interior is draught-free and quieter than any convertible I’ve driven.

There are compromises. To make room for the roof, Mercedes moved the twin bucket rear seats 50mm forward and each 16mm closer to the centre of the car. So it’s not quite as commodious as the Coupe.

If the S500 lacks the dramatic exhaust note of the Mercedes-Benz S63, few buyers are going to complain of a lack of performance – 0-100km/h in 4.6 seconds. In terms of handling finesse and ride comfort, the S500 is more appropriate to the wafting character of a big and heavy convertible. In the air suspension’s comfort mode the super-soft ride crushes any irregularities while introducing some float. Set it to a more sporting mode, though, and it instantly becomes a brilliant GT car. Your choice.

Driving the S500 is, in the words of John Carey, like riding with a mattress on top and a pillow underneath. Superb.

SPECS
Model: Mercedes-Benz S-Class Cabriolet S500
Engine: 4663cc, 90deg V8, dohc 32v, twin turbo
Max power: 335kW @ 5250-5500rpm
Max torque: 700Nm @ 1800-3500rpm
Transmission: 9-speed automatic
Weight: 2040kg
0-100km/h: 4.6sec
Fuel economy: 8.5l/100km
Price: $360,000 (est)
On sale: September