Verizon service is the worst service. I have noticed that Verizon no longer has the coverage its once had. I have visited more than 10 countries and Verizon was the worst in all those countries. They service is worst when making and connecting calls in the US. Data plan and LTE are no better, poor quality and lighting speed data speed is no-existent.
Then why do you continue to patronize the business? Also do tell of these other countries that VZW is in... Besides, if VZW has been horrible...and you know there are other options...explore them. Don't spend money on a service you hate...make sense? Thought so... Best of luck to you at your new carrier...
Since your Verizon 4G phone is unlocked for service while in other countries and has bands for international GSM, your best option is to buy a SIM card from a local GSM carrier.
Coverage in the USA is usually fantastic, but not for every area. You should start a poll: ask people around you with good service what carrier they use.