We reported this morning on Verizon's iPad data rates crushing AT&T's, but if you're looking for raw download speed instead of cost savings, it might be worth checking out AT&T.
Network World reported that studies from Metrico Wireless in five US cities showed that the iPhone 4 downloaded at twice as fast a rate on AT&T than Verizon. The AT&T phone had faster download speeds while moving, but the Verizon iPhone had the better upload speed when the phone was stationary.
For those following this since the Verizon iPhone's release, this is nothing new. A TUAW hands-on last month showed slower data for the Verizon iPhone in Los Angeles. Considering that CDMA is an older technology to begin with, the result of the survey is really no surprise. It is worth noting, however, if you're considering an iPad 2, since the Verizon models will also be CDMA.