Not really, a number of us run the Denon 3808 and I ran my M80s for a while with a Denon 1804, So you don't have to buy a heftier amp, just one that is well built. I would be very surprised if the newer Yamahas you are looking at couldn't run the M80s.
Well, the Denon 3808 at $1000-ish and 130 wpc x 7 and 39 lbs would seem to be heftier than a Yamaha RX-V663 at $410-ish and 26 lbs, no? I'm not trying to be argumentative here, just trying to understand what does/doesn't work, and to make a decision to stick with M60/RX-V668 or go M60/3808 or M80/3808.
