Chet: The 3rd can, which as Scott pointed out is US-grown San Marzanos, is my favorite. It has a deep, earthy, ripe San Marzano flavor with lots of natural sweetness. It's $1.39 for a 28 oz. can.
One thing I realized upon closer examination is the US can has some added salt (220 mg. per serving) vs. the Italian ones (20 mg. per serving). When I added some salt to Scott's favorite (2nd can, "Product of San Marzano Italy") and made a sauce, it was neck-and-neck with my favorite. It's $1.95 for a 35 oz. can.
So buy one of each and try for yourself! Please be sure to post your findings.
And as I mentioned before, the worst can I tried was the DOP San Marzanos at $2.99 per 35 oz. can. So don't bother with them.
---Guy
P.S. If you haven't tried them before, also pick up a can of Alta Cucina, about $4 or $5 for a #10 can. Probably my all-time favorite canned tomato. Very bright, American-tomato-y flavor. Some don't care for it since the citric acid does play a role, but I like the "edge" it contributes to the flavor. IMO, a sauce on a typical American pizza needs some of that tomato "bite" to be noticed under all the cheese. It's a different story with a typical Italian pizza, which may have no cheese at all or just a few scattered hunks of mozz.