I don't think anyone has to worry about fake tubes. There are only 2 companies in China capable of making these tubes and I don't think Psvane would do a fake, although a copy maybe with their own label is very possible. The two versions may be voiced differently, although I don't know why. Someone with both types will have to tell us what they think.
@danmar123 I don't know yet whether my 2 pairs sound any different. I'm waiting till I get 100 hours on the GF pair then I'll swap them into the gain stage. I only know they sound hugely better than the Psavane UK's that I replaced them with in the buffer and the Psvane UK is a decent tube. Hopefully the GF will sound a little better, for the extra cost they should!