I usually run 88oct e-15, because its cheaper then 87oct here. No noticeable change in mpg or power. I did use 91oct no ethanol a few tanks. One tank actually got worse mpg (I think a fluke, or maybe crappy fuel), the rest were all the same as 88oct.
I use 88oct e-15 in all my vehicles. No noticeable mpg change in any and its cheaper.
When I check mpg for different fuels, I break it all the way done to cost per mile. Cheapest per mile gets used.
My old Ram with hemi got quite a bit better mpg with 91oct no ethanol. But at that time the cost per mile was slightly better with 87oct e-10
