"why oh why would you want to buy a Kawai DP?!" (Laughed at by a Roland dealer)
But it's great that Kawai recognised that there was a market for a keyboard with great action for around $2500. This doesn't seem to be something Yamaha or Roland is pursuing.
The Roland RD800 with it's PHAIV action was (for it's time) a marked improvement on their PHAIII action in the previous Roland model (RD700NX). In terms of improvement in action-quality, Roland have improved the most over the last 5 years, but they still have allot to make up compared with Kawai. It takes time to close the gap in technology! I would say that by the time Roland's successor to the PHA-50 action is released, Roland will have a stage piano action in this price bracket to compete with the Kawai GFII (but perhaps not with the next gen Kawai action, who knows how much of a leap Kawai will make).
I've played both the MP11 and the RD800, I can say that whilst the PHAIV action is not comparable on weight---slightly too heavy and also the very slight squishy bottoming out [that was much more pronounced on the PHAIII and gone on the PHA-50])
---if anything, the dynamic control the Roland offers is slightly better. Indeed, the RD700NX supposedly had 128 (0-127) levels of sensitivity; whereas, the RD 800 is 100 times more sensitive i..e, 128 x 100 times more sensitive = 12,800 levels of sensitivity.
The other point to make is that Kawai concentrate on producing a stage piano for bands (the MP7) and one for the Pianist who loves realistic actions (MP11); whereas, Roland's RD800 went super over-kill on the sounds, having 1113 tones---clearly aiming their second-tier stage piano at gigging musicians.
If you want a great Roland piano emulation, you have to go with the v. expensive V-piano: having another level of quality compared to other stage pianos (due to the connection between their key-bed and their modelling technology being so involving).