Purchased a grade C1 MAC6700 a month or so ago from Audio Classics (outstanding service, great unit!, THANKS, guys). It replaced a Marantz PM7005 integrated amp, no slouch, itself (sold quickly on local CraigsList). But, the room in which that system was installed, my living room, was pretty much unused. Not so since the MAC6700 went in. I am now finding myself in my easy chair a whole lot -- listening to the TU2 FMHD tuner module -- WI Public Radio classic music service, local community HD jazz programming, also CDs, Internet radio (Classic FM from London a favorite), and just really enjoying the system. i did upgrade the tweeter drivers, and replace (Crites) the aging cross-overs in the Klipsch Chorus II speakers -- all in all, it was pri$$$ey, but completely worth it -- no buyer's remorse for the MAC or the speakers work. My first career was in the record business. Music is my first love -- and we never forget our first love. The MAC6700 reignited that flame.