GTi's kill SLK's....
Enuf said 
Not the 350 or the AMG 55 
Mine's Mullah'd more than one 350 SLK 
It would have, its got more power than standard, weighs less and has a whacking great turbo on it. Its not all about how fast you can go.
Sigh....
Ohh I'd better go out and buy a GTR as its faster.. oh no wait, its Japanese, guzzles fuel and likey to get nicked while touring europe

Oh no, wait, I'd better waste some cash on modifying a standard car to the point the gearbox plays up and it becomes unreliable.
Not only will it be unreliable, I'll have a job to sell it on, the residual value will be a lot less and it will need constant replacement parts/tuning....
But hey, its faster lol.