I like the color of the Yamaha more..
Actually once you have the PA1000 at home the colour combination is quite "chique " to say the least. Better than what you see on the pictures. the only thing not well thought off is the black buttons on the black background even if all buttons have a led light in it. To me as a home musician this is no problem but for gigging artists this may be an issue.
Both the PSR 975 and the PA1000 are superb keyboards each in his own right. If you can afford both I guess I would personally rather do so than being able to buy (only) either the PA4X or the Genos. Of course the only thing to beat these two is owing the PA4X and the Genos

As regards drums: I would say that 99 out of 100 would definitely say the drums on the PA1000 are far superior to those on the yamaha.
As regards the overall sounds and samples I keep on saying that the Korg requires much more in-depth tweaking out-of-the-box.
Hence I keep on programming on my new set of Resources.....
regards,
John