Well i'm going to use Mobil 1 EP on my next oil change with an Amsoil filter. I doing analyzes on Mobil 1 Full Syn at 5000, Mobil 1 EP at 7500, and finally Amsoil at 15,000 with a filter change at 7500. I was going to just switch to amsoil but I'm really curious to see what the tests show. Oh...