I used Impulse Tracker & Modplug Tracker in the late 90s. I tried out FastTracker, and later on used Buzz for a bit but could never quite click with it like I did with Reason.
Thanks! The Groove Mixer timing can be applied to pretty much anything - the random timing isn't dependent on quantisation. There is an awful lot more to the Groove Mixer than I've showed here, but the random timing feature is the one that I tend to use the most.