Good choice, John. I use a Marsh A200S as my bass amp, and these things are a bargain. The only reason I use the Marsh as a mere bass amp is b/c my VAC 30 watt tube amp can't power the bass as well, not b/c Marsh doesn't sound great on top!
I also hear that Marsh preamps, especially the tube version, are real sleepers. Should easily give those Bryston preamps a run for their money.