Disklavier

I am considering buying a Disklavier MX1 XG piano that comes with the
above control unit and I jut wondered if anyone has any ideas if the
control unit can be upgraded to a better version and if its worth doing
or not.
 
I wondered if anyone has a list of what kind of features these units
have, inc what the CD does in some of the high end versions
 
Thanks
 
Mark.