I was able to store three midi files in the user area plus about 15 user styles before the mamory was filled up.
The disk shuffle works very well - just wait a few measures for the song to fully load into the buffer, and then you can remove the disk. Works like a charm.
Even if they were the SAME price, the PA80 would not compare to the 2000 for ease of use and "live" playing features. It seems, the gereral concensus is that the Korg has an edge in programming, and fine editing, while the Yamaha is really a breeze to open up the box and PLAY. Given the difference in price, I can't imagine wanting the Korg over the Yamaha. (I had the Korg first - it was a work in progress then, and I know there have been improvements since.)