I have a STX1550C and 2way-gateway for sale. You would need to get a ST-CP. I can order one for you if you would prefer. The cost for the Stx1550c, gateway, Docking station, and to IR emitters is $2500.00.
The STX1550C is Brand New, I just took it out of the box to verify they sent me the correct stuff.
This is the premier crestron two-way touchpanel without going into the TPS line. The retail on this package is $6000.00 +
By going two-way you get feedback from you components, it it the only way to really know that your equipment is doing what crestron tells it to.