My favorite right now is MassFX the Destroyer. I'll argue that a product with multiple components is a stack within itself.
The major reason for the reformulation was due to the fact that divanillyltetrahydrofuran is such a tricky component to standardize for. We had a real eye-opener with a few third party tests, showing 85% was more like 10%. We researched the problem, found a superior preparation, and went with it. Now I can take 3 capsules and emulate the same effects I was getting with 5 or 6.