Replace V1 or V1-V3?

So I'm going to try out the Tung-Sol reissue 12AX7 was wondering would it be alright to put them in all three gain stages (V1-V3) or just keep what Mesa ones are in there and just clip one of the Tung-Sols into V1?

You can put them anywhere , BUT !!! My MKIV came with a mix of Tung Sol and EH 12ax7's from new, all labelled 'Russian 2' !! :shock:

Hi there.My mesa DR came with SPAX7 in V1 and Mesa 12AX7-A 7025 in V2-V5.I decided to a bit change tone so I have ordered 4 JJ ECC83S for V1-V4 an one Shuguang 12AX7-B for V-5.
I mainly play some metal stuff on Red channel/modern so I found that JJ`s are perfect mach for my style ( I haven`t try clean yet) but hum level went more than 50% up.So I put Mesa SPAX7 tube back to V-1 and result is no more hum. :lol:
About balanced tube in V-5 I didn`t find any difrence.