I use the higher octane because the difference in cost is just pocket change. If it burns cleaner and doesn't contain the ethanol.. all the better. Shobiz - when you pull that small rod out make sure not to lose the spherical ball behind it. Mine dropped out and had absolutely NO grease on it. So I greased that up too. Hey Wicked - where do you find the Valvoline synthetic 2 cycle oil? I'm using the conventional Valvoline oil which works great but I might switch to synthetic after the break in period.