I have been in this hobby for 34+ years and never use "after run oil" I just run them and put away. I will say that I believe the bearings in the OS engines are of less quality than they were 5-10 years ago. i am always replacing them in the OS engines. guys at the field that use after run oil still have to replace the bearings. I have a old webra 120, 4 OS 46's and different 25-32's that are 8-10 years old and the bearings look good.

Anyway i dont waste my time or money with "after run oil" . Now i do believe that if you use the "after run oil" and get the stuff well into the bearings where nothing is exposed to the air then will last a very long time stored.