Verizon wireless for coverage, but you need to look outside that box. I will not talk bad about any carrier, I used to work for one of the big 4, but after I left, and I dearly missed my employee phone plan, I educated myself on what the "real" cost of wireless service is.
There are TONS of MVNO operators out there that people just do not know about or are scared to use. MVNO stands for Mobile Virtual Network Operator. Fancy term that just means, you are using one of the name brand networks, just not called the named brand, i.e., Virgin Mobile or Boost Mobile, those are just Sprint Service rebaged. The best thing you can do nowadays is buy your phone outright, or buy a good quality used phone. Tons and I mean tons of places offer used phones, and they are just as good as brand new phones. The old flip phones of before are not good, but within the last year, the iPhones, and Droids, of the market have been producing phones that last. I personally tried out all my former competitors when I no longer worked for a certain wireless company and man, for where I lived, the service was just not up to par with what I was used to. I did not end up keeping my prior companies service because it was too expensive. But I can tell you there are lots and I mean lots of choices to save you money.
My father was on my employee plan, but I convinced him to buy his next phone outright so he didn't have to worry about any contracts, plus his bill was cut by 68% a month. And he has unlimited everything! I didn't want to use that MVNO, so I am using a T-Mobile MVNO. I don't promote wireless carriers, but I would be more than happy to point you in the right search direction.
The more up front, for a phone, the less you pay in the long run. 2 year contracts are not worth the headache. And certain phones like ATT and Tmobile work on each other carriers, even with Sprint and Verizon, some phones 3G phones will work, you just have to ask for them to be unlocked. The new LTE service that is launching is great, but the average person doesn't need the speed. Unless you are a heavy data user, LTE speeds is not a factor in my opinion.