Eurotubes is a store that sells only one brand of tubes (JJ) and to my ears, they don't sound that great (if you use only JJ in all positions). Too driven, too dark/muddy. I have a TriAxis/2:90 which is tonally similar to a Mark V. Not the same, granted, but enough to give me an idea.
My advice is to read a few posts from bandit2013 (I think that's the right username) for feedback on tubes, he writes extensively about them, though mostly power tubes IIRC.
As for JJs, I like one ECC83S in the V2 position in my TA. Didn't care for them anywhere else.
I like to mix and match brands, and my favorites have so far been TungSol 12AX7 and EH 12AX7. Seem to have a nice open tone, warm but clear.