Do they exist? Say you put a NOS GE 12ax7wa into the v1 of a jcm 800 and the rest are CP preamp tubes. Do you run the risk of the v2 frying faster than usual? Also, since NOS tubes pull more vacuum, is it possible for them to damage any aspect of the amps circuit if the output is too high? Long story short I bought the GE pretty cheap from a non reputable dealer who probably didnt know that it was going to be used in a tube amp. Do I have anything to worry about?