The "kit" comes from RCD and (I think) is exclusive to CCS. I've seen budget prices from CCS around $28k to upgrade to PIC III controls. Otherwise, someone with a little knowledge could piece meal the components from RCD, but (again, I think) CCS will need to dowload the software into the PIC.
Cheaper isn't better, but less expensive is always a good selling point. The manufacturers are pricing themselves out of a job as people come into the market that have the ability to "work around" the OEM platform.