What is it? Drop-top version of Merc's awesome gullwing-doored SLS coupe, the SLS Roadster allows you to enjoy both fresh air and the V8 engine's full vocal repertoire.
What's it like to drive? Awesomely capable but with the ability to intimidate the unwary or inexperienced.
Underneath that vast bonnet lies a 6.2-litre V8 that produces 563bhp, 479lb ft and a roar that would have made even the space shuttle sound a bit effeminate.
The sound is merely the prelude to a level of performance that ranges from eye-opening to gut-wrenching depending on how far you flex your right ankle.
The 0-62mph dash disappears in just 3.8 seconds, and not too long after you'll hit the top speed of 197mph. It's fair to say that straight-line pace is not an issue.
Neither are corners. The SLS was designed from the start as a coupe and soft-top, so any potential body wobbles were engineered out from the beginning.
The Roadster feels truly vast no matter how fast you're travelling, but it corners with a fleetness that belies its vast dimensions. The steering is quick, but not too quick, and that long nose follows your instructions precisely.
Grip is strong, but if you get on the throttle too hard, traction isn't. The stability system always gathers everything up, though.
There is a downside to all this unexpected agility, and it's the fact that the suspension has to be so firm to keep that vast body in check. While this is acceptable (just) in the coupe model, it isn't what you want in a roadster. Sometimes you just want to get the roof down, sit back and cruise, but the SLS never allows you to do this, bouncing, jolting and fidgeting from bump to bump. It's bad enough to make you actively avoid bad surfaces when you should have no need to.
What's it like inside?
Chopping off the roof has meant doing away with the coupe's show-stopping gullwing doors, but the upside of this is that you get to fold down the roof in just 11 seconds and enjoy the full al fresco experience.
The interior certainly feels well put together, and there's decent space for the driver and passenger, but the presence of switches and dials that appear in a 29k E-Class is a bit jarring.
The view out is also severely compromised, especially to the rear. The driver and passenger sit low in the car, and the rear deck is quite high, which means you can only just see the top of the windscreen and roof of any car that's behind you.
When the roof's up, over-the-shoulder vision is virtually nil, forcing you to rely on your mirrors, and making it essential that you shell out 665 on the optional blind-spot warning system.
Should I buy one?
If you want searing pace, a biblical soundtrack and hang the comfort, yes. However, before spending the cash, we advise you look at the Aston Martin Virage Volante and Bentley Continental GTC, both of which offer plenty of ground-covering pace with a lot more comfort thrown in.
What Car? says