That's a tad 'ex cathedra' CW.
The CP5 isn't a real piano. It's a... er... CP5. The point (for me) is whether or not it's an instrument I can play music on. For me it's the sweet spot of what's available as a gigging tool just now. But I'd like to try the MP10.
You said that the action on the CP5 was as close to a grand as you'd get, I'm just pointing out that it's nowhere near, not least because it's missing escapement. There aren't many people that'd say the top-end Yamaha's have an action that's better than the RD, being in a position to play both all of the time I'd say that the Yamaha is absolutely nowhere near. Personal taste aside, and with the addition of escapment, the Roland is capable of far more minute changes to the velocity than the CP5.