I read where so many people claim that amsoil is better than mobil 1. There are also many people who consider being better by how long the oil will last before the oil needs to be changed. In my eyes when I think of one oil being better than another is due to oil break down against metal to metal friction,and wear. I know a lot of people use synthetic in regular passenger cars because they don't want to do an oil change every 3,000 miles. For me it's all about metal to metal friction under a heavy loads. So which is better under extreme pressure Amsoil vs Mobil 1 ?