I have had a sensor and transmitter failure for the past 3 weeks. The tech support person is a complete moron. Follows a script and is too stupid to hold a tech support job. But, it gets better. The tech support person did not even record my call, having told me that he had shipped me a new sensor and transmitter. A total lie. But, even better. When I called back, the tech support person this time told me to *** off. Yes, he said I could just *** off. Stay away from Dexcom. There product sucks and their tech support is beyond pathetic. They hire *** who are nothing but useless. User's recommendation: stay away.