For a point of reference
I have Audio Note, Jolida and a few others, but the tube designer I've enjoyed listening to this last couple of years for amps and preamps is....
Especially the A25-M and the AP-01. I mention these as a reference to what I use to ping pong back and forth with the Class D world. I also have outstanding relationships for borrowing equipment. Nice to live a few blocks from the CES. So I'm not that far from anything I want.
One thing I will mention about class D is how one mates them with the rest of the system. I have heard class D sound thin with speakers that have more components in the crossover. Class D likes simple crossovers or in my case only one capacitor. As with any type of amp design using the best speaker type match is important. If folks put a class D amp into a system use to A or AB they might find themselves coming up short. Class D is a different animal and really cool design once you find the variables that fit, like with all things audio.
MG