One thing, I think is easier to use the Korg PA588 but is only my opinion, and one more issue, the polyphony is 80 in Korg and you can load 2 SMFs and play one and if you want to crossfade from one song into the other one.
The Yamaha has only 64 notes.
I think Korg has one of the fastest dynamic allocation processors in any arranger, even in the previous PAs 50,60,80 and 1Xs, had only 62 notes and I never experienced note drops on choke.
So if your SMFs are "loaded" with notes and or controllers, the Korg may be your best instrument.