Disklavier

Hello,
I have a couple of questions for this very knowlegeable group...
1) can a modern DKC50,DKC100, DKC55 or DKC500 be used to control a 
MX100 (allowing 2DD, HD, E-Seq, MIDI input)?
2) is it as simple as midiout on DKC?? to MIDI in on piano?
3) is it posible to send other voices to an amp?
4) is the only answer a DSR1?
5) is any of the these availble (DSR or DSR/$1295), at what cost?

Thank you
Joe