I've not heard of it before to be honest. I thought I'd reply to bump your thread a bit.
I've had a look on the website and it seems to be a one size fits all kind of thinking. Very american 'jazz hands' selling (but then it is american). Some of the feeding guidelines seem a bit uneducated, but that is just my opinion.
If it works well for your horse and you have a local supplier or are able to get a supply then it would be worth keeping him on the same, even just to start with.