Hey Rick, the McIntosh MC275 is one of the all time great classic amps judging by the length of time its been in production. Its a great amp to use with the M80s especially when listening to strings or female vocals. I prefer it with Classical music or jazz. Its bass reproduction is pretty good for a tube amp because of its high input impedance but still not as good as most SS amps.

The big downside of tube gear is maintenance. Failing or noisey tubes can be a PITA. I've found that Telefunken tubes sound best in the Macs and are more reliable.

John