I’ll have to agree with DigilubeJay in that Amsoil may not be the best oil, but then again, no one can tell us what the best oil is. While I have not done any UOA’s, as far as I know, DigilubeJay has not done any of his own, either. It seems, at least to some degree, that he relies on the UOA’s of another TT member to base his opinions. However, gray has also done UOA’s, albeit fewer, with differing results. The big difference I notice is that the 22 UOA’s DigilubeJay refers to are from a 250f, ridden at an unknown intensity. The 4 gray refers to are from, I believe, a 450f, again, ridden at an unknown intensity. I assume the 450 will put less stress on an oil than a 250. Of course, I cannot back this up with fact, this is only my belief, but the UOA’s referred to seem to back up that assumption. As stated previously in this thread, the conditions an oil is subjected to will vary between machines and users. To state that one oil is better than another because it was run in the same bike (it wasn’t) under similar conditions (similar is relative), is purely speculation. The only way you can determine what is best for your machine and riding habits is by doing your own UOA’s, and many of them on the same oil to average out anomalies. That being said, I am confident the Shell Rotella T 15w40 that I run is providing adequate protection. I change it and clean my filter every weekend I ride, whether it’s 20 miles or 200. Bottom line, change it hot, change it often.