I own Insta-Dry from head to toe.
7mm hood, 7mm fullsuit, 7mm booties, and 3mm gloves.
I would buy the booties and the gloves again in a heartbeat. (My 3mm gloves are warm as some 7mm gloves I have worn, and I really can pick up a dime while wearing them. Way handy for this photographer.) I might or might not buy the hood... I just don't see a huge advantage to the insta-dry material there. I probably would not buy the 7mm version of the suit again, instead opting for a full suit with integrated hood, like the Bare and Xcel suits. (Another reason why I'll pass on the hood next time around.)
The suit does dry very rapidly, as long as you hang it up. (Even plastic sheets don't dry if you leave them wet and folded up in a bag, so expecting truly instant drying is absurd.) However, if you wipe the suit down quickly with a towel, inside and out, it really will be dry pretty much instantly, even on cold days. The material they use to cover the outside does not retain water like nylon does, and the bare neoprene inside does not, either.
As an added bonus (and the primary reason I would buy the booties again in a heatbeat), my entire wetsuit, boots included, smells like clean neoprene after 60 dives in it so far this year alone. (I bought it in February... and yes I pee in my suit.) No special washing other than a quick rinse in the bathtub at home and hanging it to dry. On the second day on a liveaboard, it is bone dry by morning if I hang the suit, without any extra effort on my part.
OTOH, it is true that the external material does not wear as well as nylon-covered material. I had grooves cut into my suit from the crotch strap on my bp/w, and I haven't heard many other people complaining of this phenominon, so I think it's the suit's fault more than the stiffer-than-I-would-like crotch strap.
In warmer waters, however, wearing a thinner version of the suit and a BC without a crotch strap, I wouldn't hesistate. They're great suits. Not cheap, but very good. They're just made a little more expensive because of the wear issues.