As I stated in my previous post, I am a heavy data user and I have never had an issue with straight talk. If you pay your bill on time they will never shut off your service. Having said that, however, if you don't pay by the due date they will shut it off that day. If you buy a 3 month, 6 month or one year plan the savings are even better and you never have to worry about monthly phone bills. I pay monthly and I always get several reminders throughout the month about the service end date. I have found that Straight Talk Customer Service is as good or better that AT&T. You have some long hold times and difficult language accents to deal with, but really the only times I have ever even used customer service is initial activation, and when I wanted to change phone numbers. The service is very dependable. My son had Cricket service and it was very sporadic coverage. Straight Talk service areas ARE AT&T. The only real difference, other than cost, is you don't have a store to walk into for service like you do with AT&T. I don't think you can get the sim cards at WalMart any longer, I believe you have to order them online and therefore wait a few days to receive it. I had to cut the sim card down to Nano size for my iPhone 5 but that was super simple. You can get someone at one of the mall phone service places to do it for you if your not comfortable doing it yourself.