It all depends on were you travel and the cell provider you have.
Only 4 companies have actual cell towers across the USA
1) Verizon
2)AT&T
3T MOBILE
4)Sprint
All others use the above providers towers at some point
In the east heavily populated not much difference in service. All of the above have towers in populated areas
In the west large areas only have Verizon or AT&T service
So you need to know whose towers the others are using if you get a company that uses Sprint and you take back roads in the west you will be without service or roaming which may limit services such as internet. Worse the dreaded roaming fees