I've had a TAD 60 for a couple of months now. Mine has the upgrades. I run it mostly in triode mode with feedback off. This is one sweet amp! Bass is very good, better than any tube amp I have personally heard. Mids and treble are smooooth. Detail is excellent. I can't think of anything else in this price range that would be any better. Looks really great, too. I'm using mine driving a pair of Hawthorne Audio Siver Iris coaxial speakers (with modded crossovers) in open baffles. These amps are impressive!
Dave
Dave