Rotel seem to be mentioned a lot online, in regards to there top notch build quality, and sound quality for "Class D" amplifiers.
I've purchased an Used/2nd-hand Rotel RB-1572 and Rotel RMB-1575 "Class D" amplifiers based on lots of positive on-line reviews.
Sometimes the 2nd-hand market for these are reasonably priced as well, .......check out eBay.com, Gumtree, canuck audio mart, U.S. Audio mart, U.K. audio mart, AVS forums classifieds, Audiogon.......to name a few sites that have regular 2nd-hand listings.