If you run the fuel outta your engines at the end of the day, after run oil is at best a bit of insurance. Nothing more. Running the excess methanol/nitro out is the key.

There is one thing you all can do that will ensure badly rusted engines. don't run them dry at the end of the day, and then plug the muffler to keep the drips off the carpet. This traps the methanol/nitro inside, and bearings rust quickly. Especially if the carb is also closed, so the engine si a completely closed unit.

J