I believe they now have two models, the original and a cheaper one.
I've only tried the original and have to say it works amazingly well. Set up as per the rather detailed instructions, I used it for a bunch of voice over stuff and it was hard to tell the results from the same guy speaking in a professional voice booth with acoustics by a noted company.
As said, the set up IS important (and could result in some of the differing opinons) with some unpleasant effects if you put the mic too deeply in...and a loss of the effect if the mic it too far out.
It's fine on decent heavy duty mic stands...but I could see it being a problem on some of the cheapies out there.
I'd be interested in opinions on the new cheaper model.