I just don't understand the attraction of Sprint to some people. Their 3G is akin to 2G/EDGE on AT&T/T-Mobile, they're moving extremely slow with their LTE rollout, and they're CDMA. Even once they finally get some LTE is all major cities, there will still be that horrible "3G" network to fall back on. It could very well be 2015 before they are a viable network with consistently decent data speeds.
T-Mobile has taken their pricing and unlimited data advantage away from them. They also have similar coverage but have a much stronger 3G network to fallback on when not on LTE and are GSM.
Then for those who don't mind paying more, AT&T/Verizon just totally blow them away in all respects.
I know it's all YMMV with any carrier but every single person I know that has Sprint has nothing but complaints about the service and data speeds. It boggles my mind how they are even the 3rd place carrier. It must be because of the subscriber base they had in place prior to the smartphone age. Hopefully the Softbank buyout occurs and gives them a much needed cash infusion to improve their network. As of right now they are the only carrier of the big 4 that I would not go to with a smartphone.
My company has a discount with Sprint. It's cheaper to have 4 phones with unlimited data than it is to use a different carrier and have packaged data options. Everyone throws up the, "Who cares if you have unlimited data if you can't use it" excuse, but I have not once ran into a problem where I couldn't get something to load when I really needed it. As long as it works, it's cheap to me and I don't have to worry about someone running over on data, I'm content.