I have seen the same deals on that amp, and wondered the same thing. I have a SA-250 (Little brother) that is retired to the bedroom system that sounds great. I think there is a review of the SA-250 on soundstage.com I would think they are pretty close in over all character.
CJ Sonographe SA-400 now discontinued Any good?
Conrad-Johnson Amps in general seem to be highly regarded. But I have seen this amp (brand new) selling for nearly half its retail price of $1700 with little or no interest. Is this amp an undiscovered gem or a black sheep in the CJ family. What would you recommend for a solid state amp in the $2000 dollar range to drive a pair of Paradigm Studio 60's?