Some of the class d stuff is really good for not much dough, some is good for a lot of cash.
I'm constantly impressed by the quality of sound out of my Panasonic XR-55 with class d amps, especially the eq section (simple shelving bass & treble controls) which is one of the more transparent eqs I've ever used. Just incredible that I only payed something like $230 for it 5 years ago. Not sure what chips it uses but it has 7x100W channels, automatically bridges 2 pairs for stereo or uses 4 seperately in a bi-amp config with the correct hook up, which is how I run it for stereo.
I only wish it had pre-ins for all 7 amp channels to use them any way you like with ganged tone and volume control across the lot- it only has 5. And I wish I bought a second one.
I've used a friend's T-amp and it sounded great but just didn't have enough headroom to push the dynamics for most of my speakers. Great for portable stuff though. I'd like to have a quality portable surround playback system I can haul to backyard parties and such to play my surround recordings and I've thought of building some active 2-ways housed in PVC pipe, powered by these and DVD batts. Looks like my imaginary wireless network for feeding all 5 from a laptop or netbook for playback now exists but needs to fall in price:
Radiient Roomcaster Early Adapter Kit. My completely wireless portable fantasy project now enters the realm of possibility.