Charlie, thanks for sharing these impressions. Like you, I have found this amp to share the most enjoyable and fundamental characteristics of the fully modded SE84UFO3 Zen monoblocks I've lived with and loved for five years, and to have that extra something--a touch of lushness that is at the same time more natural and realistic by another touch. Hard to describe, easy to hear and feel.
I'm in my third month with this amp and I think it has blossomed and stabilized and I'm not restlessly exploring all its potential and nature as I had before. I've just started with a Sophia Electric Aqua II rectifier, the new improved version of the Aqua I determined was the favored one in this amp and it is a pleasant little bump up in all the factors I love about this amp. And I paid more attention to the isolation aspects of my system which also has sweetened the flavoring in just the right way.
I thought I would never sell my Monoblocks, but I was wrong. So I won't say I'll never sell this amp but I think it's the best design of Steve Deckert's yet and I'm going to be happy with it for a long time.
My next target, when I feel I can recklessly afford them

is a pair of 300B tubes so that I can have a backup pair. I've been recommended the Cryotone, but I doubt I'll go there. At present, as great as the Sophia Electric are sounding I may move to the just introduced new version, the Classic II 300B. But I'm still pondering and scheming how to afford a pair.
My current tube complement:
"Sun" made in Holland 12AU7 input tube
A pair of RCA made in Holland 7308 driver tubes
Three English made (no label) 75C1 voltage regulation tubes for the input and driver tubes
Sophia Electric Aqua II 274B rectifier
A pair of Sophia Electric Classic 300B power tubes