Hi Dan,
only reason I brought it up is, some may decide to choose a soundsource you don't have access to.
Instruments like guitars, piano's , bass etc , a substitute can be found, volumes can be altered, to make the style sound good, wheras if the drumkit used isn't mapped correctly for the style, it's not going to sound right.
Strangely enough when I converted the Ketron SlowOrch style across to PA3X , I noticed the drum mapping on the SD2 Brush Kit isn't 100% identical to the GM Brush Kit I have in my Korg.
Yet I think they're both supposedly GM.