There are at least two user groups on the web for solenoid player
pianos.  The Disklavier Users Group (DUG) is run by Yamaha and
is somewhat biased.  You will likely be advised against buying
a "gray market" piano for reasons of lacking support.  Information
about DUG is at http://www.ptg.org/disklav.htm

The other group is the PianoDisc user forum:
http://groups.yahoo.com/group/PianoDiscUser/

Best regards,
Spencer Chase
Laytonville, Calif.
http://www.spencerserolls.com/