Regarding FP30x, it got better pedal control( a little sustain /half Sustain/full sustain), bluetooth audio, better speakers, LR Line out for stage or recording.
Yeah, it is perceptible about playing these three DPs. However, which one is better? We would suggest you to play and feel them by yourself, coz it's subjective. In addition, FP30x, FP60x, FP10 are installs the same key action, PHA-4.