Would using all three supplements, Advanced Mitochondrial Formula, Metaphenol 27, and Mito-Essence, although expensive, be worthwhile for benefiting health and longevity significantly?

This would be worthwhile in providing broad coverage for this critical and central functional capability of the human body, as so many things are dependent on the bodily energy system and its working smoothly, as well as avoiding the production of noxious metabolic products that not only impair mitochondrial function but damage other critical cellular and organ functioning so as to cause alteration of DNA, for example, and thus malignant transformation to get tumors underway. The combined effects, lifelong, of a degradation of mitochondrial effectiveness are a central consequence and driving force of aging and the decline that eventually leads to death for everyone. So as an antiaging strategy, you inherently will gain from using these supplements in combination because they will plug more holes and slow multiple things most effectively which, together, conspire in leading to decline in function over time and a weakening that eventually will be a tipping point bringing about transition from the physical plane.