[lostmsu]

To add more, this depends on area a lot. Basically MVNO or not some areas would be better with T-Mobile and some with Verizon.

[ahaseeb]

Yes purely depends on your coverage areas as in few areas T Mob would be better and in other verizon or ATT. Best is to get a sense of the area you mostly spend time in. For home/office. Wi-Fi calling does the job