Danno,
Duh, I missed seeing your room dimensions earlier in the thread. No, the M80s are not overkill in a room like that, nor is the EP500. You don't need an EP600, which is wonderful for very large rooms.
H/K's measurements are very conservative and honest; they usually deliver considerably more than their rated output in bench tests. Figure on an H/K that is rated at 75 watts per channel being equivalent to a Denon that's rated at 110 per channel.
Since you don't require insanely loud playback levels, look at the Denon 2807, 3806, or 4306. The 4306 was recently highly reviewed at audioholics.com . The H/K 635 is also worth looking at.
