If so, is that largely due to FirmPlex including nattokinase? Does the hesperidine add anything significantly to efficacy?

Both of these substances contribute to the enhancement of a sexual response by differing mechanisms and as such, work well together for a heightened outcome that is synergistic rather than additive. This is true for a number of combinations of nutritional substances and other natural products that have effects on the body systems and physiology. This is only natural given the complexity of the body and physiologic regulation and function, that supporting life with its quite intricate makeup requires multiple chemical substances from the diet. And some things that are rare in nature have been put there for humans to find and use as therapies as a planned eventuality that was expected to happen and encouraged through inspiration in response to human yearnings. This is one of many things we contribute to your soul journey in the physical.