Lets hope they can keep it up. I left Sprint after 11 years to go with TMO. Im in Dallas. Ill give them credit for launching Dallas in the first wave but i will also tell you that the first 2 months i saw the fastest LTE with them, after that i was lucky to get 5 megs down on LTE. (at work, at home still NO lte and i live near down town dallas) Top that off with my device not getting incoming calls / texts. That part eventually was traced back to network upgrades and after 2 months of dealing with it i left. I wish they could have fixed the issues but sadly they are dealing with a lot of trouble shooting.
GIve sprint some time to work out the kinks. I do believe they will have a great system, or at least a pretty decent one. But when it came to the reliability of getting calls i had to draw the line and test out another network. Luckily for me it met and exceeded my needs and expectations, plus i save 20 bucks a month.