Sorry I have a opinion.No I am not carrying water for Amsoil.I have used MB1 in the past,and I learned that if a engine has a leak,MB1 will find it.I don't have ANY experience with any other oils so I didn't comment good or bad. The SS says 25k under regular use(I would not)I will stick with what makes me warm and fuzzy. I know all Syns. are so much better then 10 years ago.SS is the first oil which I seen that gave the extended OC on its label.MB1 may now but they never did before.Who else let's out that secret info? I do run the MB1 high mileage filters.Have a good day.