Has anyone here played both the FP-2 and FP-4 (not FP-4F)? I'm curious as to whether the actions feel very similar or if they are substantially different. (I know, it's old gear...)

Scott, I used to have the RD-300SX, which I believe has the same action as the FP-2. It's an ultra-light hammer action, one which I found a little too light to be truly effective for piano. The FP-4 is a meatier action, and is more controllable.

i owed an fp-2 for 5 years - loved the action. I think the fp-4 is very close - just a hair more resistance.

Did you fine the FP-4 to feel slightly better, slightly worse, or too close to care?

Are the FP-4 and RD-300GX actions identical? I see that Roland refers to them both as "PHA alpha II" but I'd like to hear from people who have actually played both, to confirm, do they feel the same?

Well, the following comment is not quite to the point. Anyway, I did play an RD300 with a suffix that I don’t remember anymore (SX? GX?) It did have the PHA alpha II action as I ascertained afterwards, since I liked the feel of the action. The most recent PHA alpha II action that I played was that of the console F-110, and again I liked the feel of the action, much better in fact than the feel of all newer Roland actions and better than the feel of any other DP action, including that of the AvantGrand N3

If there was a plain Jane 73/76-key MIDI controller with the PHA alpha II action, I would buy it sight unseen, perhaps 2 of them.

the FP-4 has better samples. I think i liked the fp-2 keyboard a little better but it might be b/c mine was broken in. But they are very close. Didn't like the rd-300sx - something weird in how it felt.