I have the comp 275hl in my 408. It sounds and drives pretty good. It definitely sounds cammed but isn't the rumpetiest, I can idle below 1000 rpm. Power comes on good in the midrange and pulls steady to 5-6k but no explosive cam 'turn on' in the upper rpms like a more radical cam.
I think I could have gone with the 285hl and gotten some more horses, but for a hot daily driver I am satisfied.
