Welcome xander!
The M60s would be just fine for that room. But, if you have a hankering for the M80s, and if the budget allows, I doubt they would be "too much" for a room that size.
The M60s have an 8 ohm impedance, and can be driven with just about any of the common brands of receivers. I think we recently had a poll of what people on the forum are using, and more had Denons than any other brand. But, Harman Kardon, Pioneer, Yamaha, and Onkyo were all represented.
The M80s are 4 ohm speakers, and are a bit more touchy when it comes to power, although they are generally considered an "easy" 4 ohm load. There are 3 brands usually mentioned for the M80s, Denon, HK, and I forget the third (old age
). Hopefully someone who still has a memory will come along and fill in the missing blank(s). I'm sure that the M80 posse here on the forum will chime in with more suggestions.
