I spoke with a man who works in Yamaha as a demonstrator about the keybed of PSR-S950, he didn't say that it's excellent, but he said that it's rather good. I asked him if the keybed of S950 is better than keybeds of entry-level keyboards like PSR-E433 and he told me that it's definitely better.

As for me, when I was working in a restaurant I had to play Yamaha grand piano there for a long time. I sure liked its action, but I can't say that switching to any of my keyboards (PSR-3000, S950, NP-30, MM6) was in any way painful after that. I admit that I'm not a professional pianist, I don't play tricky classical stuff (I don't like it either), but I do want the keyboard to let me play what I want.

If I'm not mistaken, Roland uses keybeds which are made by Italian corporation called "Fatar". I had Fatar's midi keyboard for a while. Can't say that I felt about it any different then about Yamaha's products.