I am always curious as to the performance of some of these relatively cheap high power amps which are designed primarily for "live music" use where the noise floor, unlike those amplifiers designed for use in an A/V set-up, is not really of the same importance. I have used power amps in PA and musical instrument applications for live music and once the volume is cranked up they have a fairly audible amount of hum or hiss to them.

I am sure there are some out there that are better than others but so far, the ones I have encountered wouldn't be of much use in my A/V system.