Primaluna - Rolling pre tubes question...

I've lived with the Primaluna Premium integrated for about 2 years, heres where I have settled

1) tube dampers a must... subliminal screechiness for female chorus and strings otherwise that eventually becomes irritating.
2) Kt-150's work wonderfully all around for power tubes but give up some vs EL34 on the human voice. But the EL34 can't do cymbals right.
3) Telefunken 12AU7 hard to beat for all 4 small tubes
4) Amperex/Holland Bugle Boy 12AU7 in front sockets with Telefunken 12AU7 in back is also very good and a little more mellow

Not a fan of ceramic sockets for pre tubes like the PL Premium integrated has, much prefer Teflon or composite sockets for better damping at the junction of socket and glass bottom of the tube. Microphony is distortion, pure and simple, never good.