I've used Sta-Bil for many, many years after finding out about old gasoline the hard way. I had parked a snowmobile at the end of winter and failed to drain or treat the remainder of gasoline in the tank. The next winter, on a very cold snowy day, no amount of pulling on that starter rope would start the engine. We drained the old gasoline and filled it with fresh. It started immediately and ran fine thereafter. Once I started using Sta-Bil, I never had a similar problem.

I'm pretty sure that the directions for Sta-Bil include a mix ratio for long term storage and another for everyday use.