Congrats on your FS purchase!
I've found the Amperex NOS tubes to be outstanding. I have 6922s and, 7308s, both PQ and USN. Some are Holland, (under the Philips lable) and some are USA made. All are white lable. These are sonicaly even, clear, extended and seemingly un-colored.
Emmanuel, at last communication, seemed to like the less expensive, and currently produced Electro-Harmonik tubes. Sadly, these (EH 6922 Gold Pins) don't seem to work as well in my system. I still have apair just sitting here. :( Email me if you want them.
I have also tried the Ei 6dj8, with good results. These are very surprising, considering the cost is about $20 for a pair! They are not the same as the NOS Amperex tubes, but at 8 -10 times LESS than the Amperex, they are pretty darned good.
good luck with your new toy. :-)
paul