Hell, I've been using the Rotella T6 for a long time..and before that, the regular Rotella 15/40 in my old cars. I also only use Mazda OE filters. Only recently had people on the forum I hang out a lot on, MiataTurbo, did people start doing a bunch of oil analysis and proving the T6 is tits and comes back with superb results. Personally I think Mobil1 is a big scam. Somehow or another they're indoctrined so many people to believe it is the end-all best oil on the market. I've tried to spread the word about Rotella for years.