Cassp, think again and get rid of the Casio PX as I have done with my PX560 and look at the new Roland Juno DS 88, check out Youtube demos and you will be impressed with the great sound. It has split and layers facility as well as a sequencer and good drums.
The 88 keyboard version is 35 pounds weight, I have ordered one from Thomann in Germany plus a lightweight Gator case.
Frank