I just "downgraded" from a CP4 to a Roland fp30. (Pior to Cp4, I played a Roland FP4 at home and gigged on a yamaha grand almost daily.) I couldn't belive the Fp30 has such a more piano-like action to me than the CP4. During the one year of owning the Cp4, I struggled to warm to it(sound and action) but with no success. The Fp30 also gives your finger some good workout. Switching from it to the yamaha grand I gig on is effortless. Also, I can play some classical pieces on the Fp30 with ease, while it seems impossible on Cp4(It may be just me.).I also own a Kawai ES 8,which is a beautiful instrument (better sounding than the Cp4 IMHO). But its key action is a little bit too light for a practice board, though it plays beautifully as a gigging board. So now the FP30 has my favorite action among the 3.
Now I'm a Roland guy again, and I wonder how much better the FP90 and RD2000 are than the FP30(With my respect to all the fellow mumbers' opinion here, I have to try these myself and sincerely I think you should , too ).