My old amp is/was an Emotiva MPS-1. I had a problem that one channel did not turn off with the 12v trigger. I sent it back and it came back with the same issue. I've sent it back again and they are taking care of shipping both ways. I have a prepro so with no amp I have no sound. When Acudef started this thread I started looking closer at these amps and found great deals on Audiogon and decided I would upgrade and sell the MPS.
I went into this not expecting any difference in sound and as far as I can tell that is what I've got. The only real difference that I can find is the the noise floor in non existant with the ATI's. The MPS has a very faint hiss when you stand right next to the speaker while these are dead quiet. I have to say it is the amp because everything else is identical.
I have not rerun Audyssey with the new amp and really don't see a reason I should need to. All levels seem about the same.
I should have the MPS back by the end of this week so if anyone is interested I'm ready to make a deal.