Interesting about the NuPrime, I gave up on them in the early class D years, but sounds like they have matured.
I bought a pair of M3TMs from Clayton this year at a show, he also recommends Red Dragon class D mono amps. they go for about $1000 a pair used.
I have used a Bel Canto Dac for a few years, and it has a built in preamp, which may be an excellent match with their single or mono block amps, there are a variety on the used market for great prices. Remember, Bel Canto used to build tube products, so the CEO voices to the human voice from a tubed perspective. Bel Canto has the $50k "Black" system for the last 2 years, all class D, so their class D products have matured.
It is neither hash or bright. I had one in my system for a month with the same speakers Rebbi has. IMO it is a very solid choice in terms of performance with outstanding value.