Hi Ian,
talking off the top of my head, I'd be surprised if the micro had the extenstive editing functions of the pa500/pa800, but who knows. Personally I'd sooner have the pa500, the newer styles are better.
The micro serves a function inexpensive & lightweight take anywhere, great korg starter.

Ian, when are you going to check out BIAB again, gee it's come a long way since the old midi days, though I gather you're an arranger player, thru & thru. haahaa