I can’t nor will I try to offer any attempt at answering the question directly, as I’ve never compared a SET of a certain wattage with that of a PSET of the same wattage, given the variables between the two are too great.
I can say this:
I have never liked big bottle tubes, including the 805, 845, 211, GM70 and 833 - at least not in any of the implementations I heard them.
I have also never liked PSETs using any tube (big or small), or push-pull amps for that matter (unless we’re talking guitar amps).
So despite a well-entrenched bias against big bottle tubes and parallel circuits in general, and a growing conviction that no big bottle amp or parallel topology would ever meet my criteria for ownership, that all changed when I heard an amp that used a tube that was new to me, the RCA 813, a big bottle tube of which two were used in parallel, driven by a single RCA 814. That amp is now my favourite by far.
That’s not to say I’ve changed my mind about big bottles or parallel circuits in general. Just that single variables in isolation usually tell us nothing about how those variables react and interact when brought together. Again, implementation trumps topology, and topology trumps parts selection, at least in my experience.
Is this amp you refer to the Aries Cerat Diana by any chance? Most intrigued!