I've actually been very impressed with T-Mobile.
Switched about two years ago, and the lte network has expanded really dramatically. Back then, Houston and bcs both had lte, but in between was nothing. Sane for Houston/Dallas. About a year ago they lit up lte between Houston and cs, and now it's all lte between Houston and Dallas. East Texas has improved dramatically too.
I drove to Palestine, then shreveport, and had lte probably 90% of the way.
I believe I read that they plan on having lte everywhere they currently have 2g by then end of the year.
Plus they offer the whole unlimited data thing. If y'all have passed on them in the past because of concerns over their network, it's honestly worth a second look now.
For the record, I don't work for T-Mobile. I'm just a highly satisfied customer, which I never thought I'd say about a carrier.