Joseph, do you have the Sophia rectifier tube or is your WA6 all stock?
Yes I do have the S/P-274B and 6SN7WGT driver tubes. I also have a 1959 Mullard 5V4G/GZ32, which I recently got, that also sound very nice, and I'm waiting for a 1958 Mullard 5AR4/GZ34. I've never tried the stock rectifier tube that came with the WA6 at all. I also have 6EW7 driver tubes that Jack Wu gave me in place of the stock 6DE7, and they sound nice also. I'm also waiting for the 6FD7 (fat bottle) driver tubes from Woo to check them out.
So I never listened to the WA6 with the stock tubes that it comes with at all.