If I don't know what's in it, I refuse to use it. Superthrive might be fine for some plants, but I smoke the cannabis I grow with my wife (who has been on chemo every two weeks for the past 8 years) and would never intentionally let her smoke concentrated hormones, steroids or hemorrhoids, or whatever's in that mystery goop.
If you're using a solid nutreint product or line, Superthrive shouldn't be necessary anyway.