The only generalization I've noticed is that those 20th Century Masters - the silver "Best of..." CDs at P.O.S. (Point of Sale, not piece of...) stands are terrible. They're distributed by MCA (a Universal Canada company), and the one I have here is labelled that it was assembled at MCA Music Media Studios, N. Hollywood, CA. The first track (My Generation - the Who) exhibits some major digital clipping. Other than that, I've been really pleased with a lot of Warner releases, but it really depends on where and who it's mixed and mastered by.
Bren R.