Thanks all...and Lula I hope you will eventually get an answer, although I don't think it will be on this thread.
I apologize for the direction that this thread took. I am appreciative that someone, anyone, took the time to reply to my question.
Shredder, I believe the only complete review I've read, besides the snippets on the DH site, is Garrett Hongo's. I'm somewhat surprise there's not more chatter on Audiogon about the 50A. I believe it has been available for at least a year now.
I was interested in the 50A after reading Roger Gordon's review of the deHavilland Aries 845 and the Merlin VSM-MXe. I have Merlins and I've always loved the sound of the 845, but to reiterate my room is large and even Kara mentioned the Aries 845 may not cut it.
I guess I'll have to make a road trip to Washington and compare the two amps myself.
Again thanks for the advice.