I recently got the Sprint overdrive for the ipad wifi. Here in the DC area, we "unofficially" have 4G available in spots. I have ran speed tests including the app that you can download on the ipad and consistently get around 4 to 5 mbps vs 800k - 1.1 mbps on the 3G side of Sprint. It works great and i love the fact that I can stream netflix movies with no issues or lag. Also there is no data cap on the 4G side, but there is a 5gig cap on the 3G side, which makes no sense. I verify this from time to time by checking my data usage with Sprint and it has not changed significantly from the previous time that I checked. This is due to the overdrive kicking over to 3G in the areas that do not have 4G up and running yet.