MC-1 digitizes all analog inputs--that should be all you need to know if you care about music.
B&K has had reliability problems in the past(their A/V receivers were notorious in this regard), but they may be better now as it's been about 3 years since I sold'em. Just something to be aware of--otherwise I hold B&K stuff in high regard.
That said I have to agree with Argent. If you can swing it the SP1 seems to be the obvious choice, especially considering your amps but also 2-channel performance.
There is one other option that is actually what I'd do. You can buy a relatively inexpensive Denon receiver to handle the surround processing duties only(still using your Brystons for amps) that'll do fine for movies and buy a high-quality 2-channel preamp with a home theater passthrough that will seamlessly integrate with the Denon. This way you get the best possible sound quality for critical stereo listening while maintaining upgrade flexibility(just flip out the Denon when surround formats change), and all this at a lower cost than a higher-end pre/pro--best of both worlds, except you've got two boxes instead of one. Excellent solid state stereo preamps with HT passthroughs can be had from Adcom(GFA-750), McCormack(RLD-1), Levinson, while tubes offer Sonic Frontiers, BAT, AR, Rogue, Conrad-Johnson, VAC(or VTL, not sure which). Anyway, just another option to consider. Best of luck.
Tim
