If you can afford Rotel RB-1080 go for it! I have it with M60s in a stereo setup, and even though M60s are very easy to drive speakers, more power does not hurt. And of course, 1080 will serve more than well if you decide to get M80s.

Axiom M60s, QS4s, VP100 Onkyo TX-SR804 Oppo 970HD Rotel RB-1080/RCD-1072 REL Q150E sub, PS 3