Agree with all of that, with the caveat about Tung Sols in Cathode follower positions. Several threads about it at TGP and The Boogie Board. The Tung Sol AX7 is great in V1 of many Mesa amps (and others). I currently have one in both of my Mark V's and had one in my Mini Rec and TA15, but don't put it in a cathode follower position, which most Mesa and many other amps have... And I don't know if any of the PRS amps have one or not. So just saying, make sure first.