Can't say for sure, but I've got the Denon UD-M50 and I like it a lot. I think the D-M33 isn't quite as powerful, so if you like blasting it you may want to think about the next model up or at least pair that with some easy to drive speakers.
That said, I blast my system as loud as I can tolerate and it doesn't have any problems. I'm into the same kind of music, hard rock. I've got mine paired with Energy Connoisseur C-1 speakers and a Mission MS-8 sub. I found that the sub helps a lot, as the speakers I have are very good but it's too much to ask a bookshelf like the C-1s to generate lots of clean bass. Hard rock can be pretty demanding.