I know this thread is AKAI-centric, but if you're just looking to add grit to your software based drums - get an Ensoniq DP/4.
You can pass drums through the AD/DA with no effect selected, and it gives you that ASR10 flavor. I've been doing that mostly from Cubase. You just add it as a hardware effect insert on your mixer channel.
I usually use it as a stereo effect on my drum bus. If you adjust the input knobs so the peak lights are hitting red every so often on the DP/4 it gives that nice SMACK and grit.
Here's a quick and dirty joint I did on the mpc1k/cubase/dp4/microX last night. Mighta squashed it a bit too hard with Izotope Ozone, but you'll get the picture.
cynic - Bluez - SoundCloud
PS: I'm still probably going to buy a s950 and a s3000 when I can find em cheap