I bought an iPhone 5 on Dec. 20, 2012 from China Unicom. Several days later, I couldn't send MMS via this iPhone 5, and I went to Apple Authorized aftersale service center (ServiceOne). The first time they said this iPhone has some problem and changed another new iPhone 5. Then the second iPhone 5 still failed to send MMS and I had to went to the service center again and again. The service rep had my iPhone OS restored several times but still couldn't solve the MMS send failure problem. Then the service rep changed still another new iPhone 5. Now, the third iPhone 5 I'm holding still failed to send MMS. The service rep suggested that I call Apple Care and see if I can get refund. I called 4006272273 to file a complaint and requested refund. The so called Senior Technical Support Rep MR. Jiang was very rude. He refused to take care of my refund request and insisted that I went to the service center again and again. I'm really disappointed at this kind of service. I started using iPhone 3 in 2008, then iPhone 4 in 2010, and then this iPhone 5. I never met such disgusting problem during my iPhone life these 4+ years. I'm disappointed at the quality of iPhone 5 and I request refund and compensation.