Stratocaster Case

What is the likely quality difference between a Fender Stratocaster made in America to one made in Mexico?

For example in the case of the signature series Buddy Guy?

Depends... if you are looking at the higher end American made strat, you're going to get a better set-up guitar. If its a standard strat vs. a Mexico strat, you'll barely be able to tell the difference. I think there is currently 33 different strat variations you can buy, from 4 different countries of origin. Quality control is taken pretty seriously by Fender, so they are all pretty decent guitars. I currently own 6 Fenders - 3 strats, 3 teles. The tele's are all American, but one strat is mexican, the other is mexican. While I love my American strat, from a playabilty standpoint, the Mexican made is a very decent guitar. Resale value on the American stuff holds up way better than the Mexican. Personally, I'd find a 1982 "smith" strat. Fine guitar.