Say the magic words...."Gain Cell". 
Quack! Quack! Quack!
I've gotta hand it to PS Audio; there market-speak obfuscation is the best! These are the folks who call a CMC (common mode choke), their UltraOutlet, a Balun....
"A Gain Cell is the culmination of 25 years of work and thought wrapped up into a single module. A Gain Cell is the most revolutionary piece of audio technology I’ve been associated with in all the years I’ve been involved in our audio/video world."
It may well be the culmination of 25 years of work, just not work by PS Audio. So they take a TI THS4131 differential amp (or TI'sr TPA audio specific version) and wrap it in a Wolfson (for that 'stretch' [at best] claim of non-attenuating volume control] WM8816. BFD.
This is not to say that it isn't an excellent approach, it would depend on the implementation. Revolutionary? Hardly. But if it pulls one's pizzle string, go for it.