I'm not to keep on most of the fore grips out there. Very little variety (mostly tube variants). I was looking at my umbrella today and thought "man, I'd really like to hack this handle off and make a fore grip out of it". Did a quick image search for umbrella handles and discovered tons that would make awesome grips:
So yeah, if somebody could make some kind of clamping (or any other method you can think of) umbrella handle adapter for Mags, I would buy a couple.