My wife and I spend a lot of time in zip code 21719. Our Straight Talk phones running off Verizon towers do not get coverage. The Straight Talk website said that the iPhone 5S would work perfectly. We bought two of them. They still don't get coverage. Since our home is in zip code 17356, they set it up for Verizon towers again. When questioned, we were told that we would need to change our phone numbers that we have had for 20 years.
The phones are not unlocked. If we paid cash for them, why would they be locked? This is getting frustrating!