Generally speaking you are talking 1-2% difference e10 vrs e15
In reality for me at least my economy is the same or ever so slightly better summer and a couple mpg worse in the zero F winter
Thus at $3-$4 gas you are guaranteed the same or better at 8 cents cheaper in all circumstances, depending on your car your break even may only be 3 cents
Me personally (depending on the car)
I won’t run it if I’m not saving more than 5 cents a gallon especially in the winter.
My one car that demands premium gets e15+ all year
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