i agree with woolly bully, its all the same. i have read that and seen it , its all the same but they do put in different additives in it. i have had my yamaha 115 jet drive for 12 years now,always ran premium and i have never added any stabilizer to it. i always run chevron, i have never touch my motor except plugs and filters. i run chevron in my trucks and rv and have never had a fuel injection problem in over 300,000 miles??? maybe just dumb luck..