Luke Edwards is an excellent demonstrator for Korg. However in the guitar demo which I think is the third video there seems to be some confusion about how many insert effects can be used simultaneously on the Korg PA4x
You can use 5 inserts efefcts simultanously...
4 on the style, drums or song parts..
And one that can be assigned to a single keyboard part..
There is also 5 master effects.
3 for styles/song parts and 2 for keyboard parts..
Unlike the Tyros, you can not play song and styles simultanously...