It's hard for me to describe in words how much I enjoy my M80s.
15 years ago I had a very good pair of Dali floor-standers. I really liked them, but they never evoked the kind of emotional "Woah..." response that the M80s do.
My first impression was the sheer sense of power that the M80s convey (there was a thread here where someone called them "Towers Of Power"). They produce extremely strong, tight bass and they are clear and accurate across all frequencies. In my room they present a huge sound stage, both wide and deep.