amsoil is actually a really great company, they stand behind they're products 100% and from my experience they are the best out there. the creater of mobile one used to be an employe of amsoil. amsoil was originally used in military planes because they found that it was the only oil that wouldnt get burned up. i know one person thats such a believer in amsoil that he put it in his brand new f150 and only adds one quart once a year when he changes the filter and that is all, he has never yet done a complete oil change and he has over 250,000 miles on it. seeing this is what sold me to it