Interesting product, from what information I can gather about it, it would probably be a reasonable way to get silica. Although it is very expensive. DE is far cheaper, and has many other uses, in the garden, with pets and livestock, etc.
The product is patented so its not possible to get the formula, this means there is no way of knowing (unless you get inside information) as to whether this product could be harmfull or not. Basically you are relying on the manufacturers claims of its bioavailability and effectivness.