Honestly, they both suck. The main chip has been downgraded on both from quad to dualcore. They increased the battery by 150mAH on the Sprint version which is cool but not that major of an upgrade! Sprint's version is a fugly device when compared to the original One X. AT&T on the other hand kept the elegant design. Me personally, l will be getting an unlocked version and unfortunately, AT&T is the only compatible service provider with the same frequency so I would be able to get 3G but not LTE. In a couple of words, HTC screwed the US HTC users. Coming from a user who has been an HTC fanatic for over 9 years.