The PA80 will drive you nuts, considering how you just described yourself. I think the Korg is a superior synth, and handles smf playback better than the Yamaha, but geting around on it is a different story. The Mic input on the Yamaha has more gingerbread, and the harmonizer is more refined.
I just traded my PA80 for a Tyros, and I'm still uncomfortable with some areas, but overall...the styles are what I was after, so I'll try to adjust to the shortcomings.

For those of you snickering in the background ( you KNOW who you are ) this was not a move to attempt to make me happy. Just to make me some $$$$$$$. The Tyros is brand new and hot right now, and I can turn it around in a second. It's just a profit deal. I can play anything at work...this is just the KB du jour.