I should mention I kinda wish I went with 33's. With 35's I'm having some balance issues that the tire place cannot seem to fix. It's just too much distance from the wheel rim to the tire.
As far as MPG goes, I measure before and after. 1mpg loss, after accounting for how the bigger tire effects the odometer reading. 8.5%
I lose more MPG when I run the Air Conditioner in the winter.