My '72 140 came with the mogas STC. I haven't used mogas in it yet but have been thinking about giving it a try. Previous owner said he mixed it 50/50 with 100LL for awhile, but got tired of the hassle and just used avgas. I know the big problem is ethanol, but assuming I have a source of non-corn juice gas (and also check it to be sure), what have been others experience with using it? Any issues, etc. Have you noticed and difference in gph vs avgas? Saving $1+ per gallon is starting to look pretty tempting about now.