I've got the PS Audio GCC-100 tricked out by Cullen and love it driving my Magnepans. I think it has been the longest I've ever stayed with a single amp, and there have been several over the years (Adcom, Counterpoint, Audio Research, Audio Refinement, Muse 300 monoblocks). I love the spacious, open sound and great control it has on the planar bass panels. Just picked up a pair of big high-efficiency "constant directivity" speakers with pro drivers, and initial impressions are equally positive, though this gives me a chance to try out some low-powered options including tubes and chipamps.
I also have one of the original Wyred Ice Cube 200-S amps, which I believe was their first product. Essentially a tricked out PS Audio Trio Amp with modifications done to the input board (which actually says "PS Audio" on it) and a pair of the little ICEPower 200ASC modules (the GCC-100 uses the 250ASP modules). I got it primarily for rear channel use, but have not had surround set up for some time. I definitely prefer the GCC, but that may be due to differences in the input stages and added power of the GCC. Still exhibits the same general characteristics, just a smidge less open, detailed and unrestrained.
I'm definitely in the Class D camp and have been partial to the ICEPower amps, but I'm also interested in trying out the DIY options via classdaudio.com (there's a long thread about these in the Cheap and Cheerful forum). Played around with TriPath via Sonic Impact, which work surprising well for $30, but more a novelty for me good for a desktop system and not plausible in my main system with such limited output.