The McCormack's are fast amps but I agree with Timo, lot more to it than speed. For example, the Belles 150a Hotrod is not as quick as the McCormack but it is also fuller and richer sounding that makes music sound more like music. They're a lot of good amps on the market now. System synergy is more important than any of the other gobbly-gook(ie; what speakers, preamp and source(s).