What we're often hearing from many higher priced class A/B and good quality class A amps, are amp designs that intentionally emphasize or overemphasize the even ordered harmonics, which tends to be perceived by humans as a warm coloring added to the music that many individuals prefer.Very well said. It's all about the implementation and the expectations.
Better class D amps generally have a very accurate, detailed and neutral sound quality, with little to nothing added or subtracted to the musical signals that results in a very high degree of faithfulness to the recorded music. This is something one needs to experience to make sure they enjoy this type of amp design and sound signature, since it equally and accurately reveals good and poor quality recordings without prejudice. You may prefer some added coloring either through the amp or via tubes in the dac or preamp. You won't know for certain until you hear the differences between them with music that you're very familiar with.
All the best,
Nonoise