Hi Bestboy4,
Thanks, Johnk, for pointing out the dubious benefits of biamping in a domestic setting. I've never been convinced enough of its merits to bother with it on my own systems, because I never detected audible improvements in comparisons I heard.
But don't be concerned about the "maximum power ratings" of the speakers. As Johnk pointed out, the worry is using amplifiers with too little power--and the danger of driving them into clipping distortion--rather than using too much.
You can try biamping if you want. See if you think it improves things. The M60's are reasonably sensitive, and have quite low distortion up to perhaps 100 dB SPL, which is much louder than you should ever listen at in your room for more than a few moments, unless you want long-term hearing damage.
Regards,
