I have the Roland FP-3, which is the predecessor to the FP-5, and lacking the built-in speakers and has fewer patches than the newer FP-5. They have the same action and same piano sample, however. I also own the Yamaha P120.
For pure piano, the Yamaha is the winner hands-down. For versatility, the Roland is definitely better. By versatility I mean that it has far more sounds, though several are merely entertaining - many are quite useful depending on your needs.
The action on the Roland is much, much, faster, much easier to play in general. The action on the Yamaha is more true to the real thing, and in my opinion allows greater sensitivity in quiet passages.
The piano sample in the Yamaha is "bigger" with more character and body - richer. The Roland is "clearer" with quite a bit less going on outside of the primary, and is a bit less fun to play loud - because it just gets... loud. But some people hear both, and feel the Roland has a more "pure" sound.
If your emphasis is truly Piano - the Yamaha is the winner.
If you need more voices, play other styles or need synth sounds - you really ought to look upward to the Roland RD-700 and a small amplifier, or even better, the Yamaha S-90...
Keep in mind - the built-in speakers on all these pianos - are nearly useless... they might be okay for playing with a small acoustic ensemble (like acoustic guitars and hand drums) but that's about it. Intolerable sound for day-to-day practising.
The Kawais offer too few voices (32 polyphony!?) and the Korg action feels like mush. Neither were an option for me, the instant I played them.
Cheers and good luck!