As a rep I have seen very few problems. T-mobile had many more problems. The only thing I have seen is people being billed for 2 months in advance instead of 1. but that only happened once. Otherwhise it has been the best to deal with. Many people think their bill is wrong but never actually go through and read what the charges are and they all add up correctly.

Most so called billing problems arise from the fact that a lot of customers dont understand advance billing the proration it entails. I.e. if you start service on the 13th, and your cycle date is the 25th, you have to pay from the 13th to the 25th, plus the next month, for both monthly service and features 🙂