EXPERIENCE 1 (See experience 2 below)
I had a very frustrating and time wasting experience with Apple ... in particular their store in Regents Street London. I had bought a brand new iPhone 5 for my wife. However, when she started using it the receiver was abviously faulty as the sound was scratchy all the time. I booked at support time at Apple. I went there, and they confirmed that the phone was under warranty, they tested the phone, and confirmed that it would be repaired or replaced within next half hour. So I went for a walk. When I returned they said that they had found a wire missing inside the phone, and concluded that someone had tampered with the phone. I referred to the reseller and explained it was a brand new phone wrapped in the normal packaging. But, they still denied. After consulting with the reseller I mailed the phone for repair. The repair was done with no further discussion, and we have a working phone again. But, I wasted half a day on Apple's arroganza. One star ... maybe they will eventually improve the customer service.

EXPERIENCE 2
I eventually got a replacement unit cf. above. After three months the head phone jack didnt work anymore. I tried several times to book a genius time slot in Regents Street. But, when I had picked an available time and entered my personal info ... the website tells med the slot is gone. It did so 5 times in a row. Then I went a week forward to a day where there were plenty of open slots. Same same. Very efficent customer service denial function. The solution is to go to a non Apple repair shop. And you know what ... then all warranty is over. I must do another try with Android ... this arrogance must be punished.