PCWorld magazine recently did a detailed study of 4G LTE data speeds in 20 cities across the U.S.: http://www.techhive.com/article/2039452/atandt-has-fastest-lte-service-t-mobile-off-to-strong-start.html. The not-too-surprising result is that AT&T has far and away the fasted LTE connections, while Verizon's significantly slower network is much more widely available. Basically, your choice is between mediocre connection speed pretty much wherever you go and blazing speed if you happen to live down the block from it.
They studied urban centers only, not suburbs, small towns (depending on your definition; they did look at, for instance, Ann Arbor), or rural areas. We live in metro Atlanta, and at home and driving around town we'd probably be better off with AT&T. But in my wife's workplace or at our place in the mountains of western North Carolina, it's Verizon or nothing.
This has been the situation for awhile, and I wonder if it ever will change. Maybe AT&T will extend its network and VZW will improve its network and we'll enter a golden age of wireless data connectivity. Or not: the article ends with a quote from an expert who says, "Wireless users can expect to see the performance gap continue to widen further—perhaps to as much as a factor of ten times—in the years to come."
