HEAT did offer more, but it lacked versatility, most notably due to the tyramine... And those who are ultra-sensitive to PEA would have reactions to the hordenine. Decimate is compatible with any stimulant without having to concern yourself with catecholamine overload, which, during dieting, would be counterproductive.
We went back and forth between the 10 and 20% and decided on 10 for a couple of reasons... One of which is cost. We're doing our best to ensure quality while considering the customer. With the 10, too, the daily dosage yields 75mg of the active, which is still at the higher end. Even if we went with the 20%, we would have still included it at 75mg/day, but then it would increase the retail cost by a couple of bucks. Any amount over that, and users would be all over us for giving them the Hershey squirts.