Balanced vs standard power

Searching for an Isolation Transformer 10 or 15kva. I have the budget for Equitech but I'm sold only on the benefits of isolation and not "yet" on the benefits of balanced power unless one is recording live musicians. My rationale is that most if not all audio components are not designed with balanced power so they may be optimal performers with standard power and lesser performers with balanced power. Until someone does a side by side comparing isolated balanced to isolated standard power we may never know.

I have read the various threads regarding isolation transformers from Equitech 10wq, MGE Topaz etc, and the Euqitech stereophile review. For larger non-balanced options there is Ultra K 600 with K factor correction and triple shielding from the Controlled Power Company. They range from 5 to 25 kva.

I think supersizing Isolation transformers for audio is not well recognized yet because no one has done the necessary review/ comparisons to determine the performance curve of Isolation Transformer size to Audio Performance. Although Isoclean advocates the use of two of their Isolation Transformers for each piece of equipment. Maybe they're trying to tell us something or just sell more transformers. 10 KVA is "plenty" for my system according to Martin at Equitech, but "plenty" is not quantified enough to convince me, so I 'm leaning toward the 15kva on the Ultra K 600 from Controlled Power about $4000 vs Equitech 15 kVA at upwards of $14000.
Interesting question about the harmonics. Personally have doubts about any kind of harmonic filtration below 1 KHz for any passive technology, not including regeneration, but I'm not an expert and ferroresonance has it's mysteries. Don't have an oscilloscope to do any testing either.

Shared this link before with the caveats of the author affiliation and date.
Here are the links I posted above.
I'm interested in balanced power, and I have a question I hope you guys might now. I have two amps that I like to run together, but the hum like crazy when both are plugged. I know the issue is because one, or both, are not wired in common mode.

I have been reading some papers on the Equitech web site about this issue and they claim balanced power will solve this problem with no equipment changes needed. Not that I dispute their claim, but I'm having a hard time understanding how it would clean up the ground circuit after current has entered from down stream. What do you guys think? Would balanced power connections safely isolate these amps?
I think I get it, but see what you guys think about this. My two amps hum because they reference ground at a slightly different potential, and that creates a small current between them when they are on the same circuit. The balanced connections assure that all components plugged into it reference the same ground so there would be no potential between the amps.

Yes? No? Smoking crack? :-)

Just curious have you ever checked the two amps for the proper AC polarity orientation?

Ground loop hum.