HZPiano
nwu , Hello and welcome to PianoClack.
I recently 'felt' (but not actually played with sound) PHA-50 in an FP-90. It is said to be a great action but I immediately concluded it is not my cup of tea. It makes a strange squishing sound and has a feel to match -- it is not for me.
If you're new to (digital) piano like I was almost two years ago, and want to use your Roland as a MIDI controller with VSTs, as you seem to, then PHA-4 is a fine place to start. I chose the FP-10 because its keybed and MIDI output were all I needed. I preferred it over other slabs at a similar price point such as P125, ES110, Korg D1 and the Casio offerings.
I may want to upgrade to (for instance) the VPC1 because by now I know that for me playing piano is here to stay for probably the rest of my life, but if I can't upgrade (yet) I'll happily paddle on with the little Roland some more.
The mantra (essential!) is to try each instrument on your shortlist thoroughly yourself. All forum posts and YouTube videos in the world can be educational and help you think about your purchase, but the final decision can only be made under your own arms, hands, fingers, ears. I recently rediscovered the truth of this during several store visits -- where everything I thought I knew about all the digital piano brands and models was challenged instantly in just a few keystrokes. I was actually shocked how little (almost none!) of the current offerings I actually liked, and am glad I started using virtual pianos (just one, really) right from the beginning.
Cheers and happy decision making,
HZ