Hay buddy.
Yeah, I love the cleaner mains of late night listening, was great when I lived on a country property. Not as easy to do in a unit in suburbia now, unfortunately
Ah, I am a tube type deficient kind, and haven't used any of the RCA, Tung Sol and other NOS tubes or even the new production 6SL7 types so I can't compare. What I can say of these is they have that basic even handed presentation that the common ones have, they just seem to do everything a little better than the common ones.
That's straight out of the box (or cardboard and paper wrap in this case).
I only got two tubes so have them in the input and output positions in the EAR clone. I'm not sure if these are worth the price some of the stores and sellers ask, but I'm happy at the lower price I paid.
So bottom line is that... with nothing much to compare with, I'm not much help. I don't think they are going to WOW! people with any one aspect like some of the NOS tubes do.......again I am only speculating.
I wish I could be of more help.
Edit: Hehe...one thing this change does reinforce for myself is, that I... like the rest of us here am not affected by expectation bias as much as some folk believe it does across the board, with everyone. I had read some people on the net saying that these tubes blow all the NOS British, European and American ones away! So these experiences are always valuable in one way or another