[Arran]

I'm curious as to how the Chinese 50's sound and perform. I know one guy who hates the Russian tubes because he claims they sound crappy. I have used a few Chinese tubes in the past and they sound just fine, but have heard they don't last as long.

Well there is more then one maker of Russian tubes, there is Svetlana (Called winged "C"), Sovtek, and perhaps another. Then there is an American outfit that procured the use of the Svetlana name in the U.S through legal sleaze and is rebranding ramdomly sourced tubes with the name. I can't comment on which Russian brand is best, I did repair a guitar amp with Russian tubes in it and it sounded fine, I think they were Sovtek but I'm not sure as they were rebranded as Fender tubes. I did find some Ukrainian made 6V6s at a garage sale once, new in the box, and they sounded just as good as their U.S or Canadian made counterparts.
When it comes to tubes and audio equipment a lot of it is the electronic eqiuivailent of wine snobbery, Geman and British tubes are the best, American tubes second, and everyone else's is junk especially if it's new production. The reason I compare it to wine snobbery is many will believe that a bottle of wine is better because it costs more and because of the lable, but in a blind taste test they can't tell a $15 bottle from a $50 bottle.
Regards
Arran