You’ve pretty much nailed it. The difference was pretty minor, and my ear isn’t refined enough to pick up very subtle differences. When I got it, I had a tech who is one of *the* guys for amp work in Dallas/Ft. Worth (although they’re a dying breed, so the competition is scarce) give it a run-through. He went with JJs on the preamp, trem and power tubes, and a Tube Amp Doctor one for the rectifier. His rationale was having had good experience with those brands for those applications, rather than running up the tab experimenting with vintage tubes. He has it sounding great, and being an expert, both with the technical aspects and an ear for this stuff, I suspect he got it darn near good enough for a hack like me.