From a straight performance point of view at normal listening levels, in a normal sized room, with normal amplifier power, and using a subwoofer in your system I would not see any need to get the High Power version. Our main reason for bringing out the High Power versions is a recent resurgence in 2-channel systems. A lot of people are either setting up dedicated stereo systems or listening to their music collection in straight stereo as opposed to using a surround mode. Some of these systems utilize large power amps with no subwoofer; these sorts of setups should definitely use the High Power version. The advantages are a more linear bass below 70 Hz and a much higher maximum SPL before distortion or compression. If you are using your M60s or M80s with a subwoofer crossed over at the standard 80 Hz then these advantages will become somewhat moot. There will still be some advantages in maximum SPL above the 80 Hz crossover point, and if you have big amplification in a big room it is certainly worth considering the High Power version even with the subwoofer always in play.
Edited by Ian (10/29/13 10:56 AM)
President & Chief Engineer