For purity I'd have to vote for BMW's Motorsport division. For what I like, a little more relaxed performance and better styling/more luxury I'd vote for AMG. I've always looked at it this way, BMW's M models are better track cars, which Mercedes' AMG builds better road cars. Audi tries to do both with the S as road cars and the RS models for the track, plus their AWD slant which really makes them "any road" cars. They're all special to me, but for the hard-core enthusiast I'd have to say Motorsport BMWs have the advantage.

M