I really think any amplifier technology will sound good or good enough, as long as it's a well developed product with some effort and money put into it. Some class D's are half bridge and some are full bridge, and you can look at class A, B and AB and look at the way those amps function with their internal component layout, and the full bridge class D amps actually seem to function more closely to a typical 4 channel amp, with the way the amp boards are laid out and such. I say this in relationship to mid range and tweeter performance. Some class D amps are internally wired differently than others, and the power supplies inside the amp function differently, with the way energy flows through the board and your 12v system.
So, my point is just still that I think you're going to get what you pay for. There's a lot of amplifier types, and most of them seem to work well, as long as they are actually well designed/produced products. Just study the amps specs and company reputation, compare the amps, and try to find a price level of amp with the power you want that will produce the quality of sound you want.
