I was at the MGIA trade show the other day and got into a conversation with the rep from amsoil. He was recomending to me that I run there 100:1 premix and it wont void the manufacture warranty. I know that all of the 2 stroke equipment that I run is 50:1. Does anyone out there run this oil and have a preferance between Amsoil synthetic $40.00 a gallon and Conventional $10.00 a gallon. I was thinking of switching to it but don't know about running 100:1 and spending 4x as much money on oil. I am thinking of going to their synthetic oil for the mowers because you would only have to change it every 750-1000 hours compared to the 100 with conventional! What do all of you think?