Talk to Albertporter about this. He has heard them all, and currently has the IO DPS Signature with all NOS tubes, and knows what you want to know.
Aesthetix Rhea vs. Io Signature
Having read most of the posts re: the Aesthetix Io (both with and w/o signature and dual power supply upgrades), I think I understand its excellence, yet have not auditioned it. However, I'd like to keep things fairly simple from a heat/maintenance/no.of boxes/cost standpoint. Thus, my interest in the Rhea. Would those of you who have experience with the Rhea vs. the Io comment as to the distinctions. The concern I have is how much body, weight and richness of soundstage is sacrificed vs. the Io (let's assume with single power supply, signature version).