Anyone familiar with ARCHOIL gas additive? Went to a show and shine last night and was talking to a fellow next to me. Had a 500+ cu in Hemi with 12.5 : 1 compression running on 91 octane with ARCHOIL as an additive. He swore by it. It seems to be fairly expensive for a bottle but you use very little per tank. Any thoughts from the collective?? jerry