My choice between the M80 and M60 came down to my unwillingness to tempt fate with my Onkyo. I was told (by Alan, I believe), that I should be OK with the M80's as long as I didn't push them too hard. I'm pretty sure I would have been fine in my room, but I also feel that I'm not missing anything by going with the M60's. And I have piece of mind that I can crank it up without fear.

Dave
Audyssey Setup Guide