I've not tried very many 2A3 tubes in my Welborne Labs Moondogs , but the best sound I got was with the " mesh Plate " Sophia Electric 300B with 2.5 volt filaments that work in any 2A3 amplifier . More of everything compared with either of the NOS I tried or the Shuguang 2A3c . The driver tube has a lot to do with the sound, as do the coupling capacitors . But the latter aren't plug n play . FWIW
Joe
Joe