The technician that ruined your amp12 board shouldn't be believed for anything.
I believe they must have seen the amazing work at NP Audio, and come up with their solution.
Excellent move and great for us in next iteration of amp boards.
It should be more optimal, and also there was one other cap brand besides the custom ibasso and the "Cornell Dubelier" you mentioned.
This one has a bit less length.
And:
This one a bit longer, and not as ideal as the others.
By not choosing any of the caps mentioned, this leads me to assume ibasso was very selective in its choice cap. I expect it to be optimal size and spec.
We don't know how the new board will look inside, or how these caps will be implemented, but ibasso going thru such efforts is a big win, and I must assume will be superior to past stock amps or other "discreet" amps from competition.
It is now visually obvious Ibasso is using better parts than competition. It started with the 3Max amps. We simply don't see this type of "audiophile parts selection" elsewhere.
Large Quality parts are more solid choice than the current "fad" of "nutubes", but even with the " nutube" implementation, I trust ibasso will excrete maximum potential...