I haven't got any true notion of it's value relative to what you see paid for some ARC solid states, of that era. I own(ed) a couple of broken ones. I have seen others including mine which have been very unreliable. Approach with caution, don't pay Mac money even those these sound better to my ears. My D100B made great bass it actually lasted a year or two. I liked it for its sense of brute strength though it's power rating was about the same as those and it preceeded these models by a year or two. These are much bigger physically with what appears to be the basic ARC philosophy - tons of capacitance but with an unusual added sophisiticated METERS section. I just tried to buy a D-120, but it was DOA. I paid $350 for a well used D-100B and was going to pay $400 for the D-120. I'll do some research.
