I too was bowled over by the sound of the Orions. By far the best sound at AXPONA.
The 3D demo gave me a headache, and the sound was not that great, nothing to do with the amps I expect.
BTW, the sound of the Orion was due to the speakers. I have heard the DIY Orions with the ATI amp and the sound was really impressive. A Bryston amp, no matter how good it is, will not turn a poor speaker into a great one.
Two systems useing Bryston amps shinned above the crowd. The Orion speakers driven by two 9B SST2 oh my!!! For me the best sound of the show. The other a 3D HT [ JVC] with Theil speakers. One of the best HT setups I have experienced.
My Nervosa is perking big time and just now must try a Bryston Amp in my system. Being a tubed guy and now SET fan these Bryston amps have changed my mind.
Now which one ?? My speakers [ Pipedreams] are 94db efficient but have 24 tweeters and 9 midbass drivers pere side. 
charles