I totally agree with John Tuttle's comments but wanted to add just
one additional one.

I am opposed to removing an existing reproducing system to install
a new solenoid player.  If you choose to install a solenoid player,
please, please, please, either install it in an instrument where the
reproducing system has already been removed, or in a standard piano,
as I believe that they have made adaptations to the systems for this
capability.

An additional disadvantage of the E-Roll system added to an existing
(player or reproducing) piano is that your system is only as good as
the weakest link -- if you need to rebuild the player piano, then your
E-Roll system will not play either.

Eli Shahar