My Cary integrated uses a pair of 6sn7's also, so I got about 4 pair of that tube that I really like, and as I mentioned, I use 6cg7's in the Cary's pre spot (rather than 6922's), so I'm set for a lot of tube rolling fun. But its great that both my amp and the MW Transporter uses the same tubes (the Cary uses a pair of tube rectifiers as well, basic is the 5u4, but right now I'm using a nice pair of Mazda gz32's).
I will likely just go thru my stash of 6cg7's in the Transporter once I get it burned in, but I really like a warm smooth sound, so I'll likely want to roll some of the 6sn7's in it soon.
Thanks again!