I use a local cell provider, but get to roam unlimited on ATT & TMobile when I'm out of state. Local cell providers are awesome; amazing service, good service & prices, etc.

The only hiccup I've found is international calls on roaming are insanely expensive. I had a $100 phone call to South America roaming when it would have cost ~$10 in network.

https://en.wikipedia.org/wiki/List_of_United_States_wireless...