Disklavier

What is the difference between a Pianodisc and a Disklavier system?  I
purchased a Wurlitzer baby grand with a PD-120plus system a couple
months ago and out of the 5 piano dealers I went to no one even
mentioned Disklavier.  It is too late now but after seeing my piano a
couple friends want to purchase one and I would like to steer them
towards the best product.
Thanks,

And I apologize in advance if I upset anyone by bringing up another
product in a Disklavier group.  I don't know if piano groups are like
auto groups where people frown on other makes of cars.

Thanks,
Tony
Tony@...
Chicago, IL