I've never had experience with tung-sol preamp tubes, but I read good and bad reviews. I would just get one or two and try em if you got the spare cash.
I will tell you this, I traded my V1 & V2 12AX7 out for SPAX7-A tubes, and my Roadster runs alot quieter and the gain is not as fizzy as the Mesa's are known for being at lower volumes. It also seems to be slightly tighter and more focused as well. I am considering changing all 6 tubes to SPAX7-A just to test it out. I have read a few people doing it and loved it, and others not so much.