oh well. I actually read a post that said the opti 2 caused a engine failure but who knows conditions
there has only been a couple of people that claimed to have issue with opti-2. also most of the arguments with opti-2 is what ratio. i was using 72:1. i just put in a tank of 100:1
but i'm not here to convert you.
go to your local lawnmower sales shop. (not a box store like walmart/kmart)
they will have tons of oil & tell you why the one they use is best.
go with it.