What is Quicksilver Dri-Fuel's shelf life approximately? Will Dri-Fuel serve the purpose of StaBil? Can or should both be used in the same fuel? I?m ready to treat a 6-gal batch of fresh fuel. I?m finding what I know is fresh StaBil and Dri Fuel over a year old. I only burn 6-12 gallons of fuel a year, which contributes to the additives getting old. Thanks In Advance! jow