I was'nt going to post a review because I'm not an expert or even that knowledgable about stereo eqipment, however I can tell good sound when I hear it. These amps replaced an XPA-3 for my two main speakers, Jamo c809's. This system is in a very large room with built in cabinets partially seperating it from a dining room and kitchen, entry way, stairwell and cathedral cielings. I have another set of speakers in dining kitchen area sharing the same signal, these are smaller towers, Jamo cornet 185's, I now have them on the XPA-3. Before getting the new amps I was thinking of adding a sub but the low end now is so much better on both sets of speakers I dont think I will bother. The soundstage seems much larger more three dimensional throughout the whole space, I really am impressed. I have read how they sound better the more time you get on them I've got about 100 hrs on them now I can't imagine it getting better, the detail and clarity is impressive. I can't imagine anyone being dissapointed with these amps. That's really not much of a review but wow am I happy with the purchase.