Most have encountered bugs, namely the messages not sending issue. The question becomes what is a bug and what is an anomaly issue. Generally if it is repeatable it is a bug, but if it can't be isolated and repeated it could be just a one off anomaly related to wifi, cellular, or environmental issues and not a fault of the device itself. I have encountered wifi and mail issues but not sure of it was network related or device related as there were provider issues in my area at the time.