Ok, so here's the status of my search: I'm creating a big spreadsheet with specs and certifications for all the oils mentioned thus far. In the interest of fairness and honesty, Amsoil ACD will be included. After all, others may want to consider it and I'd like to know what I'm potentially missing. Once I'm done I should be able to make a more educated decision. I'll be happy to add any other oils to the sheet, so if you want to see a comparison between the oils already mentioned and another of your choice, post it up! Once complete, I'll try and find a way to either host either the original document or a picture of it here for all to see.
Hopefully we can all gain something from this.