The specs for all of these amps are readily found online, but in a nutshell they offer considerably more power for the dollar than "home" stereo amps. Aside from the appearance of some of these Pro Amps(some are kind of industrial looking), they also are usually(not all) fan cooled which may or may not be an issue for you at lower levels in an HT setting. There are numerous forums online on either swapping to a quieter fan or attenuating the existing one. Still, if someone is adding this kind of power to your system, you probably listen at higher levels anyway and wouldn't hear the fans.
