Sprint is the slowest us mobile carrier but they've had free 2g roaming in Mexico and Canada and recently upgraded that to 3G I haven't tried to use them outs

Sprint is the slowest us mobile carrier but they've had free 2g roaming in Mexico and Canada and recently upgraded that to 3G I haven't tried to use them outside of those areas (and tbh I wouldn't expect it to work since it's not gsm) but for traveling in some subset of the Western Hemisphere, sprints not too bad.