Buy new tubes, or use "stock tubes?"

I'm considering purchasing a YS Audio Experience A2-SE. I have read reviews of different pieces, as well as different users and some say to replace the stock Chinese tubes with US or even Russian tubes. Does anyone have any experience with this matter. One member told me he replaced with RCA tubes, but heard no difference. As I said, I have heard this not just with the YS equipment, and not just Chinese tubes, but understand different brand tubes on different equipment can really change your sound. What about it ladies & gentlemen? One more thing: I read a review of the A2 SE and the owner said he was going through a set of tubes every 6 months!! In reviewing other tubed equipment, I understand it's not uncommon for a set of tubes to last years. (??)