Cytocycle: I actually had the 501 Jeff Rowland's also along with the Bel Canto product. There was so much hype gong on about "D" amps including glowing reviews especially regarding the Bel Canto 1000's that I had to get some to try for my self. I always had the Mac's along with other gear such as Audio Research Ref 300's, VTL 7.5 pre, Avalon Diamond speakers but in second system. I was trying to really simplify the Eggleston set-up and appearance wise the "D" amps were a great fit.
Regarding the Bel Canto and my current set-up of Audio Research Ref 3 and Mac 501's you just can't compare. I started going into detail but deleted it, the "D" gear is not for me or I would have kept everything. Even during the process of actually selling the product potential buyers were asking my thoughts and what I was replacing them with and I told them how I felt. They were better than a Krell 300i integrated amp that I had but that was about it.
I am very happy with my current set-up but I do want to try some other amps down the road, Dodd (New one's), Lamm, Cat, new Moscode amps coming out are on my list. I sold my ARC Ref 2 MK2 pre and I have to say I preferred the midrange over my current ARC Ref 3. I have a Supratek pre. that I am wanting to compare against the Ref 3 but had some problems from the get go and awaiting for a new replacement.