t-mobile

I've used with no problem from high point to cape may....not being a total fan boy, I've experienced occasional dark spots...like on sandy hook or out in the middle of nowhere nj fishing.

edit:

I've also used the phones Hotspot to tether to a tablet/laptop...no issues.

..IIRC, no charge fir using in Canada or Mexico....there was additional costs for Europe (Ireland, Wales, Englandn, Switzerland, Austria, Italy, etc...service was spotty in Europe.