Hi Rikki,
yes having the ability to dynamically trigger fills is a good thing (was available on the PA1x too), as were the other fill options..The Korg's really do give a player a huge amount of editing range, even to the editing and even the creation of your own sounds from scratch!!! They are great tools..I have kicked myself pretty much every day from the day after I sold my PA1xpro...but THAT is soon to be rectified!!
cheers
Dennis