Herbert has a Sprint Unlimited Data Plan, but he's got bad Sprint coverage and he roams a lot. He gets roaming charges and even gets cut off until the next month. Leo says it comes down to getting a carrier that has good coverage where he is. As a trucker, it makes sense to pay close attention to coverage maps. All carriers have their quirks. Leo recommends T-Mobile because he has an unlimited plan for $70, and because it isn't widely used, he seldom runs into slow downs.