have it and LOVE it. But I understand that you have to be within ear-shot of a large city or Interstate corridor. Not for small towns...
I have unlimited EVERYTHING, including data, and I use about 15GB of data every month. I can't do that with any other carrier. I tested my bandwidth the other day and got like 38Mbps/sec. Turned a coworker on to them and he likes them as well for the same reasons.
I do not recommend T-Mobo if you're remote, but if you are within a decent sized town/city, then go for it.
I have a straight talk mifi for times when I'm at an offroad park and need service, I buy the 1GB card at $15 at a time and mine uses the Verizon service.
LOVE T-Mobile, but understand their limitations.