Anybody have experience with NOS 6gh8/6gh8a's?

I converted my Dynaco ST70 for 6gh8's as small signal tubes replacing the original 7199 configuration. I would like to know if anybody has experience with any NOS 6gh8's and how do they sound? For example, differences between different brands of tubes. I am particularly interested in finding out how RCA's and Sylvania's sound.

I have some Bugle Boy 6gh8 equivalents, I will post results with these tube as soon as I have the amp up and running. I just finished overhauling it, and will test it tomorrow.

I am interested in the 6gh8's, though. According to my Internet research, they sound better than equivalents.

Any thoughts? Thank you!