I've tried T.J. Clark's minerals. I didn't gain any particular benefit from it that I could note, but I only used it for a month or so. The thing which impressed me the most, however, was the horrible flavor.... On that basis, I (probably) won't be buying any more, but anything that QuackWatch attacks must have some value....
On the other hand, some of the criticism of Wallach in that article does have merit. It is terribly unfortunate (or, if you're a Conspiracy theorist, terribly "convenient") that Wallach has gotten himself involved in the Utah mineral supply.