For what its worth, i live in a cold climate where rust is a common thing right next to the sea etc, i have always used 3in1 oil, fill the carb open slide and do again then give it a quick bump on the box for 1 second, no rust issues.
if i run the engine dry and leave it even for a week, it will show rust on non-dlc cranks, then will start showing on the bearing.
byrons, werks, sidewinder... they will all rust if the conditons are met, additive to stop rust is only effecting performance of the fuel.