Sean,
For what it's worth...
My friend bought a P-60 about 6 months ago. Recently one of her keys sticks as you described. I wondered if maybe a guitar pick fell in between the keys. She said it was very unlikely. And now I see your post. Hmmmm.

I've been playing my S90 for over a year and the keys are fine and feel better than the keys of the P-60.

Peace
Bob
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