There's the full rundown on what version has what. That site has that for pretty much every phone as well. It does have 700Mhz, so when/if 700Mhz LTE is deployed around you you'll be able to pick it up. The ATT version has more LTE bands, but the T-Mobile version has more HSPA bands (1700 is missing from ATT). It really doesn't make sense to get a version other than your carriers version for band support most of the time as while a given version may have more bands, your carrier probably isn't using them anyway. If they were, their phones would include it as well.
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