Good question. I too noticed all the chatter about it on the Bowsite, but it seems most of it is coming from people that are trying to sell it, which makes me skeptical.
Due to natural whitetail curiosity, I'm sure the stuff works on some deer, maybe smaller bucks. However, they make it sound like all you have to do is spray the stuff and the deer come running. We all know that is certainly not true.
I've never been a big scent guy. I've had most of my success, especially with big bucks hunting them on their own terms and not disturbing an area with new scents or attractants. I just hunt creating the least disturbance possible with regards to scent, sight and sound, with the exception of some grunts, rattles or breeding doe calls when necessary.
Anyway, if anyone here has used it, I'd be more inclined to believe their commentary than what I'm seeing over there.