It really depends on your location of use and how far from interstates you travel, when you do.
In my case, there is absolutely NO coverage for T-mobile at my lake home on any provider except Verizon. Considering we spend ~40% of our summer months there, this is a necessity.
We also travel, by car, over 3500 miles each summer on a road trip. With Verizon I have never been out of coverage; however, AT&T and T-mobile cannot keep pace--not even close.
Recent research has tended to show that the Abominable No-Man is being replaced by the Prohibitive Procrastinator. -- C.N. Parkinson