They really are both very good speakers. If you're not listening to them side by side, I think you'd be very happy with either. I originally auditioned the M60s and was blown away by their sound. However, I didn't ever want to ask myself "what if" so I jumped in with both feet and got the 80s. Needless to say, I'm quite happy with them. The good news is, you'll be happy either way. The bad news is, like all of us you'll obsess incessantly about the decision for many days before making it. \:\)

Epic 80-800: HG Cherry