Regular or high test gasoline

Most gasolines come from the same pump at the refinery. The guy that delivers to a Chevron station, according to what I was told, carries a container of techron to put in the tank.

Your Ford manual will tell you to use regular gas and I suspect has an 87 octane requirement. There are those that will say that "X" brand of gas is better than Cheapo's. Don't know. Call Ford if you want there current specs.

Use regular. If you want to save gas (not sure why it matters right now since gas is virtually free) you just need to slow down.

High test gasoline is for high compression engines that "ping" or predetonate when using low octane gas. "High test" or premium has more octane which slows down the rate of the explosion. Actually it has a little less power produced, not that you would notice it, but it won't help millage.
That said gas with ethanol has less power also. In that case the premium (if it dosen't have ethanol) could result in better milage.
Is it worth the extra money? Not usually.