Tried only that I have now (6S4A GE and 5751 GE) and stock tubes. I firstly got 6S4A GE tubes and 5751 GE I got only a two week later, so for two weeks I lived with only stock power tubes changed (the stock power tubes didn't have firm label on them, so will call it "no name" 6S4A) to 6S4A GE and it was clearly an improvement, it was like it was cleared some veil on sound when I changed power tubes, so I will recommed to try to change all the tubes if it's possible...
I will take you advice then, just bought 8 NOS NIB 6S4A GE tubes from ebay.
I love how it is so cheap to buy new tubes for the GES! I only paid 36 usd for all 8 and that includes shipping to Sweden!
In other news, I just got a package delivered from japan.. My SR-009 finally arrived :)
Pricejapan didn't answer due to their holiday apparantly, so no worries there.
Also I managed to save over 2000 usd by choosing pricejapan over buying them new in here in Sweden. Not bad!
Just waiting for my woo ges and metrum octave now, should be here next week probably.