I start to get the shakes if I ever get below half a tank ( according to the needle on the gauge ). Filling the tank and timing can be a ^$^#$^ as more ethanol is being consumed VS pump and there are few E85 stations near me.
The only time I try to run as empty as possible is when I store for the winter then fill up with 93. * There is only 1 93 station within a 30 mile radius. And finding a station that sells 93 is like turning on the radio and hearing "thriller" and immediatley changing the dial to another station and hearing "thriller".