Computerworld took Verizon, Sprint and AT&T's 3G data services for a spin all around the tri-state area—500 points in NY, NJ and CT—with data cards from everyone and an X300 to determine the king of 3G. Surprisingly (or maybe not), AT&T was the snappiest of the bunch in both average (755Kbps) and top data speeds (1.6Mbps). Of course, there's more to consider: As we've said, only Sprint gives you unlimited data freedom; Verizon and AT&T have 5GB caps (they're squishy, but they're there). Also, EV-DO has a bit wider coverage area. But if you're mostly roaming around the NYC area, it looks like AT&T might be the new go-to, especially if speed is your main concern. [ComputerWorld]
FYI, they don't really enforce the 5GB cap unless you're eating through 500GB/month for months at a time. They don't even have an overage charge for going over.
The "cap" is there so if you're an @$$hole user who torrents off his 3G, they can stop you without violating their own T&C's.