Yeap, the C220 and C2200 are also in the list. They set the bar against which I'll judge other preamps such as the Capri, Lamm LL2, Aesthetix Calypso, Audio Note M2, etc. I noticed most Virtual Systems with MC275 also run either C220 or C2200, though, which has me thinking maybe I'm getting just too creative...
My speakers are B&W 804S, and tubes are genrally a good match for my taste with those aluminum tweeters. BTW, I also have a REL (Storm III). I have rolled in upgraded small tubes for the MC275 (KT88 pending). Seems our taste might not be that far off. You have a nice system. One day I'll dive into vinyl, but before I need to upgrade so many other parts of my system!