The Accuphase looks like an implementation of the Pure Power idea, one I first saw from the guy who makes Jensen audio transformers.
It's very neat and very efficient.
It tracks the incoming waveform and actively corrects it. As a result, it is high current, and high efficiency, without resorting to an AC--> DC --> AC reconstruction process like PS Audio uses.
I can't tell you how it sounds, but if it has the Accuphase label on it in the US I'm sure it's expensive as hell. :)
I'm not sure if PurePower is still selling or not, but if you are interested in that technology they are worth looking up.