Great choice.
The only complain I have, is towards the cheap Chinese stock tubes.
But "we" roll those anyways.
A while back, I've auditioned Zus.
The amps in the room were Atma-sphere S-30 and Melody M2a3 monos as I recall.
IMO, Melody monos presentation was more convincing.
Do not get me wrong, S-30 is very nice amp but Zus just sing better with the right "melody".