Rogerwalk - I have the MC-1 and am about to trade it in on the MC-12, so I don't have any direct experience yet with the MC-12. However, if you can afford to go that route, I doubt you'll find it lacks compared to anything shy of a dedicated very highend 2-channel preamp for music. It has analog pass=thru (the MC-1 doesn't) for up to 6 channels. I have not seen any reviews, but I've read a fair amount of user feedback, all very positive. If you enjoy HT, the MC-1 enjoys the reputation of being the best in that department. Many feel it lacks in 2-channel audio, though I find it to be excellent. The potential subtle improvements of a dedicated preamp vs. what I believe the MC-12 will deliver is definitely not worth the cost, complexity or space, at least to me.
One local high-end shop claims the new Krell HTS2 outperforms the KRC-3 as a 2-channel preamp. No experience on my part. -Kirk