I know this isn't a direct comparison since the valvoline is a semi-synthetic, but I've tryed and tryed, and can't find the full synthetic stuff anywhere around my area. Anyways, if you guys had to choose, which one would it be? I've heard guys rave about the Valvoline stuff on here for a long time, but the M1 looks pretty stout from what I've seen, and its seems to be gaining popularity around here. Also, I know i'm getting specific here, but does anyone know the HTST of the M1 HM 5w-30? They list it for the other 2 grades, but theres no data sheets on the 5w-30.