Hi Ian
I am talking about the feel of the keyboard, the Yamaha has a very light touch whereas the Roland has a heavier touch, (Go back through various posts and you will find some players prefer the heavier touch of Roland whereas others prefer the lighter touch of Yamaha) the Korg is in the middle.
Manufactures swap and change the parts they use with different models, and the last time I checked (Which was about a year ago) Korg were using Fatar keybeds. (As do most European designed and manufactured keyboards)
Regards

Bill