I'm writing this on my third MacBook Air 11". First one had a defective microphone. Everything else worked just fine. Called Apple, they sent me a new one. What's interesting is that they didn't even want the defective one back first, they trusted me. Once I had received the replacement, the courier called me and they picked up the old one. The replacement had a really bad wobble / squeak. Called Apple, I was pretty disappointed at this point, and Apple understood my frustration. They sent me a third machine. I used the second one at this point and once the third machine reached me, the courier came picking up the second machine. Anyway, all this happened very quickly and pretty effortlessly (oh well, I don't like to get through two replacements to get a proper working machine, but Apple handled this really well in my opinion) Now I'm happy.