I really don't see any performance benefits...like I had said, it is wise chess game played by the oil companies and gov't alike. It was sold to be better on emissions, which it is, but at what trade off? I personally don't think it is worth it. I know many people who have ka24's and RX7's here (VA now) and no issues at all. I'd say its your car (check plugs and temps). Tune up time? My best friend had an 84 RX7 and never had an issue with it on e10. Yes, the cars will go down in performance, slightly on e10. My butt dyno didn't notice my 6 whp loss on the same tune (at the time the daily was only 218 on our shop mustang). Tuned up and couldn't get 1 hp back at the same boost.

Shit, my old beat as 1980 SR5 corolla doesn't have an issue with it.

I'm am curios as to what the fuel temps are getting up to down there? you guys still only in the 80's? temp has been one reason FL (and parts of texas) has waited so long to swap over.

I'm really curious as to why you guys are having issues?...let me know how your plugs look, gap and temp range.