I personally am not a fan of it on my two DSH. Their instructions say to use it in a circular motion, so it seems more of a massage therapy type thing. Though my cats are more tolerant of that than the furminator, all it does is produce a lot of hairs that also get loose and up in the air...and that makes me a bit sneezy and get the awful eye/nose itch.
That's my personal view on it, but I do know some people prefer the ZoomGroom over other brushes/combs. Perhaps it depends on the kitty and user itself though. I've only used the slicker brush, the ZoomGroom, and Furminator to compare it to.