Starting the SLK requires nothing more than twisting a key, but it's worth savouring. On the second turn of the ignition the needles sweep round the dials and the warning lights illuminate. The small pause after the final turn only makes the V8 exploding into life that much more exciting. The whole car rocks gently on its springs and the driver is left with no doubt about the SLK's potential.
Move the chunky auto shifter across, down and down once more to get underway, pause to check for traffic at the first junction and... what's happened? The V8 rumble is silenced at any given opportunity by the most aggressive stop-start system ever encountered. Three-point turns can see the car cut out a couple of times as you shunt the rather cumbersome lever around. It's a strange experience, though we certainly won't be complaining if that's what it takes to get a 5.5-litre V8 under 200g/km...
Out on the road, it's again that engine that dominates. Though its torque peak arrives quite high, the SLK hauls from lower revs with more conviction than the Jag, always feeling suitably over-endowed in the best AMG tradition. Furthermore, whilst it doesn't have the same feral appetite for high revs as the M159 6.2 with its lightweight internals, this is no low-revving V8 slugger; it chases peak power at 6,800rpm hard with a wonderful bassy roar and real energy. Its 421hp leaves the 340hp Jaguar not only trailing on the road, but also serves to make its shoutiness look ever so slightly contrived.
Unfortunately, no other part of the SLK package can match that V8. The AMG Speedshift auto isn't fundamentally bad, it just feels rather sluggish when faced with the F-Type's ZF 'box. The steering doesn't deliver the same feedback either, and consequently garners less confidence in placing the car. There's less composure to the way it tackles a road also, floating and squirming where the Jaguar remains largely unruffled and poised. Again, it would take a harsh critic to call the SLK bad, but the F-Type simply exposes its weaknesses as a sports car.
However, the brakes were one part of the SLK's dynamic repertoire that did leave a negative impression. The pedal feels fairly soft and sinks a long way very easily. Even slowing down, the engine doesn't go unnoticed as the front pitches under its weight and the ABS cuts in early. It's perhaps the biggest advantage the Jaguar holds from a driving perspective.
Despite a few fleeting moments of brisk dry weather utilised for the photos, most of our time with the SLK and F-Type was spent in appalling rain and at night. The SLK definitely holds an advantage here as its hard top does a much better job of insulating the cabin from outside. Quite a few times in the F-Type it felt like a drop or two of rain had made its way through the canvas roof (they hadn't, don't worry) where the SLK felt like any other coupe. In Britain, that's a useful asset. It also feels that bit more wieldy than the chunky Jag when not hooning around, and is fairly discreet in this company too.
Exactly because of its flaws, the SLK55 is an endearing car. It isn't a great AMG product, it isn't a great sports car, but the little open V8 hot rod remains an appealing curio nonetheless.
MERCEDES-BENZ SLK55 AMG
Engine: 5,461cc V8
Transmission: 7-speed AMG Speedshift automatic, rear-wheel drive
Power (hp): 421@6,800rpm
Torque (lb ft): 398@4,500rpm
0-62mph: 4.6 seconds
Top speed: 155mph (limited)
Kerb weight: 1,690kg
MPG: 33.6 (NEDC combined)
CO2: 195g/km
Price: £55,335
