This an an excellent thread with lots of contrasting views. I have recently auditioned the NuPrime ST-10 and the Red Dragon S-500 class D stereo amps. I thought they both sounded excellent, no question, and they run very cool. After about 60 hours on both of the amps, I swapped my McCormack DNA .05 Deluxe class A/B amp into my system and I was amazed that someone was again present in the music that was not there with the class D amps. Maybe it was just the distortion, no idea, but the McCormack amp seems so much more engaging to my ears.
To wit, I took the $1.8K Red Dragon over to my audio-fool friend's system to swap for his $10K ARC Reference 75 SE tube amp and he actually prefers the Red Dragon to his this ARC amp! He has listened to it for a week and still loves it. So, the thing of it is that you would be well advised to demo some of these class D amps to see if they are to your liking. If you go the class D route, you no longer with have a "room heater" and can forget about the hassle and cost of replacing tubes, which is a huge plus. There is a lot of like about class D amps, but to my ears, they leave out something in the musical experience.
To wit, I took the $1.8K Red Dragon over to my audio-fool friend's system to swap for his $10K ARC Reference 75 SE tube amp and he actually prefers the Red Dragon to his this ARC amp! He has listened to it for a week and still loves it. So, the thing of it is that you would be well advised to demo some of these class D amps to see if they are to your liking. If you go the class D route, you no longer with have a "room heater" and can forget about the hassle and cost of replacing tubes, which is a huge plus. There is a lot of like about class D amps, but to my ears, they leave out something in the musical experience.