Nols, welcome. As Randy's reply above indicates, there's no need to think that you have to "match" a receiver and speakers. Power is universal and works with all speakers. As to the M60/M80 question, the M80 would have the ability to play a bit louder in a very large room(which you don't have)and would have a little deeper bass extension. It also is slightly more sensitive and so requires a little less power at a given sound level than does the M60, but the 2150 has more than enough maximum power capability for either at any reasonable loudness level(watch your hearing), so this shouldn't be a determining factor.
