I just today recieved a Grant Fidelity buffer made in China with two 6SN7GT Chinese tubes. The sound is nice. I would say if the tubes you have are quiet, then 'tube rolling' is just wanting to play around with your toys.
Searching out tubes can be fun and frustrating, as you really have to depend on the unknow quantity that you are buying OLD, often used tubes. My take on it is most small tube owners keep the best for themselves, and sell the lesser ones. I plan on using the tubes that came with the unit i bought.And only in the future, if i need tubes, will I buy more. One thing I am certain of, Chinese tubes are getting better, and they will be up there with the good tube makers, and perhaps wind up being the best of all!
Searching out tubes can be fun and frustrating, as you really have to depend on the unknow quantity that you are buying OLD, often used tubes. My take on it is most small tube owners keep the best for themselves, and sell the lesser ones. I plan on using the tubes that came with the unit i bought.And only in the future, if i need tubes, will I buy more. One thing I am certain of, Chinese tubes are getting better, and they will be up there with the good tube makers, and perhaps wind up being the best of all!

