Best tube rolling options for VAC Ren MkIII preamp


I have read most VAC threads on Audiogon and pieced together some information on tube rolling for VAC 300.1a and VAC preamps (Renaissance Mk III is what I own). Was hoping to get in one thread others' experience/POV/advice on what the best tube swapping options have been for their VAC gear, or other high end amps/preamps that take similar tubes (e.g., 12AX7, 12AU7, 6sn7), or if stock tubes from VAC ended up being the best choice. Thanks in advance for any insights. If I'm missing an definitive thread on this pls redirect me.
podeschi
Podeschi,

How can you come to a conclusion on a NOS tube after 1 hour of listening? I guess you don't believe in break-in period? :-):-)
Not on a nos tube. I didnt need more than an hour with stock input tubes to appreciate their sonic character. Unlike components and cables i havent heard much change over time with tubes even my sophia 6sn7 tubes. Maybe my ears are not evolved enough. :-)
Podeschi, I have to disagree with you on this one. In my experience I have not heard one tube that doesn't change over time sonic wise, normally 50-100 hours so I feel you are missing out big time. Heck it tacks 40 minutes for most tubes to be stabble!

My 2-cents worth anyways
My Recently added seimens 7308s into my Ren sig mk2a made a huge. Difference - deeper and tighter bass, more extended highs, etc. Overall a much better, well balanced sound. Wouldn't have believed it out of 2 tubes.

Added Black treasures as the front 4 tubes for each 300.1 about a year ago. Got slightly sweeter,more extended highs.

Good luck.