Joining the flagship gullwing coupes at the very top of the Merc range, the Roadster is a stunning object.
A long arrow nose thrusts the gunsight badge forward of the snarling fascia, and from there the carbon-fibre body streams back over straked sides to the short tail.
Gullwing doors cue back to the famous 300 SL of the mid-1950s, but are hinged to the body to account for the Roadsters folding roof. From one end to the other, and down to the elegant turbine wheels, this is meant to be an eye-catcher.
It takes a lot to attract attention on Sunset Boulevard in Los Angeles, where locals yawn at the daily parade of celebrity vehicles. But as we headed towards Laurel Canyon and the freeway down toMalibu for the test drive, you couldn't help noticing the Mexican wave of swivelling heads as the McLaren's sleek form glided past.
The beauty isn't just skin deep. Lift the lengthy bonnet and you reveal the piece of jewellery that is the car's heart; a front mid-mounted supercharged 5.5-litre V8 that develops a mind-numbing 460kw of power at 6500rpm and 780Nm of torque at 3250rpm.
That takes care of getting the car to 100km/h in just 3.8 seconds and to a top speed of 322km/h.
SLR stands for Sport, Leicht, Rennsport (sport, light, racing) but the McMerc weighs in at somewhere north of 1800kg. You don't, however, get any sense of that on the road.
Provoke the throaty howl of the engine and the car ricochets down the bitumen like a guided missile. It tracks through corners as if on rails and reduces long straights into short blurs of scenery.
Gearshifts are slick and joyous and there's such instant, knife-sharp response to the steering wheel that it becomes dangerously tempting to try to chuck it harder around corners on what is a very public road.
Surprisingly, the cabin is reasonably quiet with the roof down. It's possible to make conversation at nearly normal voice levels even at ludicrously high speeds if you feel that anything you have to say is more listenable than the sound of that V8.
It should be noted that this is not a car built for comfort. You might want to spend all day burning up the highway, but in the end the leather-lined carbon race seats will get you with their lack of lumbar support.
On the other hand, the SLR is a truly visceral experience. You feel the engine changes mood through the seat and straight into your guts. To have extra padding shield you from that pulse would be as silly as showering in a raincoat.
But the main downside of the McMerc is it will only ever be left-hand-drive. So there's no room for it in Australian showrooms, although a couple have reportedly been brought into the country by owners who keep them for track days.
Nobody's revealing what it cost to ship them in, but with a price of close to $500,000 in the US, plus an arsenal of import taxes, you couldn't expect much change from $1 million. And those lucky few who can afford to get them on a track here probably feel like that's a bargain.
Snapshot
Mercedes SLR McLaren Roadster
Price: about $1million
Engine: 5.5L/V8 460kW/780Nm
Transmission: 5-speed auto
Performance: 0-100km/h: 3.8 seconds, top speed 332km/h
Economy: 14.5L/100km (claimed)