Only if you intend to listen in 2.0 mode will the M80's prove any different than the M60's. The M80's will be louder and a tad bit deeper in FR.
You indicated that it will be a 7.1 system, meaning a subwoofer will be present. Now you will probably be crossing over the mains around 70Hz +/- 10Hz. If that is the case, I say get the M60's and put the difference towards a sub that will "blow the clothes off"...
Edited by agarwalro (02/14/07 06:55 PM)
Behringer 1030A, SVS PB-12 Ultra, Etymotic ER-6i
PS3, SGT 10.1, Sansa Clip