Hey guys, I'm sure this is something that has been talked about before and a lot but I just wanted to get some of your inputs. I have actually being using Motul synthetic oil for my car and it has been excellent! I tried amsoil for the first time after setting up an account and I used their 5w-20 signature series (the one they say 25k miles which I would never do) Its been 5,600 miles so far and that oil is dark! I want to give the brand another chance so ill probably do another oil change very very soon. What has anyone who has used amsoil experience been? I am wondering if its the application of the sho, or the grade or something else maybe.