They were sold at the same time as the Art Series stuff for a lot less money. I actually sold a few at Sound Advice. Its been a while but if I remember correctly they didn't have regulated power supplies, or less regulated than the Art Series anyways. I don't think you got twice the power when halving the load.
You'd probably have to ask Isaac as how they compare to the Art Series in SQ, but if you plan on running one at 4 ohms on a set of components I'd think it'd be pretty close.
Sure wish Directed would open up more of their old school PPI pdf's to the public. Would make things much easier.