I have been using Amsoil for years and it beats Mobile1 hands down. there is a lot of independent data that shows Amsoil does a better job of protecting your engine. Amsoil was the first fully synthetic motor oil marketed. Mobile1 European blead is not readly available while Amsoil is produced locally within 3 hours from where I live. It also helps that I am a dealer of the product and have it shipped directly to my home.