I have been using a c52 for about a month.
It's not running with a Bryston amp, but I did own a Bryston amp at one point.
The c52 sounds huge. Enormous and dynamic. It's musical and articulate and a heck of a lot of fun to operate.
The Bryston amp I had was, at the time, too bright for my system (speakers with ribbon tweeters). Thinking about it now, the combo would actually, probably, work pretty well (the c52 has an EQ and one could tweak it a bit if the Bryston remained bright with the pairing).
I've owned a lot of pre amps and a lot of equipment and the c52 is one of the very few pieces of gear I've inserted into my system and have been pleased with since day one.