I run 80 front and back. On my previous set of tires I ran 55 front, 80 back, but when I got these new tires I figured I'd give 80 up front a try. No real noticeable difference in the ride or handling. Physics dictates a slight increase in fuel mileage, but there are too many other variables to calculate the difference with any certainty. Variables like more weight from day one from the addition of the shelves (previous tires only had to deal with the shelves for the last half of their tread life), which will decrease fuel mileage, so more likely any increase in fuel mileage from the 80 psi up front is mitigated by the increased weight.
Also, the previous set of tires, I rotated those every 20,000 miles, and at rotation there was no discernible difference in treadwear between the front and rear. I've rotated these once at 37,000, and there was noticeably more treadwear on the rears than on the fronts. I don't know if that's due to decreased treadwear up front because of the higher pressure, or an increase in treadwear on the rears due to the added shelving weight. I'll be interested to see if the treadwear catches up after another 37,000 miles. And if so, as I expect it to be, it'll be interesting to see how the life of these tires compare to the previous set.