I've had my M60's for 6 or 7 weeks now, and I think they sound great. Plenty loud, and plenty bass. I had someone over tonight for an audition, and we mostly played music in Yamaha's "Direct Stereo" mode, which sends the sound to just the two front speakers without any processing. My guest thought they sounded terrific (I'm pretty sure he will be placing an order soon), and we were both impressed by the bass coming out of 6.5" woofers.
I had checked the calibration on my speakers ahead of time so that the sub was at the same output level on my sound meter, and as we switched back and forth between just the M60's and the M60's plus sub, there wasn't really a huge difference. At least, the difference wasn't enough to make me think that the M60's would be inadequate without a sub for listening to music.
