I tend to agree that it would be unwise to put unknowns in your fuel tank. The fact that neither site would allow me to post queries as to the chemistry involved leads one to further believe that while they might not be total scammers, they certainly are hiding something. As I stated earlier, after researching the other posts on this forum, I was able to determine that all they're doing is basically mixing filtered WVO and kerosene plus their additive; a legitimate fuel for running diesels, but not as good as biodiesel or running heated SVO probably and the additives are not essential to the fuel production process.