Go to Ratingen to visit Racing Dynamics. They have an R54S. That's a car based on E39M5. R54S makes 515 HP. They also have an 480 HP M5 engine on E46 chasis car. Now, those cars will eat any AMG cars, supercharged or not, for breakfast, lunch,and dinner. The good news is, those conversions are available in the Europe as well as in the US.