Figured I would chime in quickly to say how elated I am with my SA 6.3. It is far and away the best amp I’ve had in my room, and possesses tube-like qualities, musicality and smoothness in spades. Together with a PA 5.2 running NOS tubes, I am getting incredible performance. I plan to upgrade to the PA 8.3 at some point but would really like to hear it first. I have mention that the factory 803T tubes that come with the PA 5.2 were.. Not. Good. lol.. max performance is significantly higher with NOS tubes in my experience.
Frankly, I am surprised that there is not more info circulating about these products. They ought to send more out for review, I think.