Coverage depends on where you are located, and the areas you frequent.
As for a general consensus, Verizon has superior coverage over TMobile and Sprint..but it comes at an increased recurring cost.
I travel between CO, NJ, and TX a lot and TMobile has been awesome, in terms of coverage and speed.
If TMobile works for you, it'll be great and save you some $$ too!
Best way is to try pre-paid.