I always buy at least two Apple devices when purchasing new. Their quality control is bad. Inevitably there is always some issue with the screens - be it dead pixels, dust, or whatever. Never occurred to me to purchase two phones, however.
Just purchased a 5S not too long ago and the first one had a dead pixel, the genius saw and agreed and exchanged it for another. The second one had a weird "pinch" effect along the top edge of the screen as well as clicked when the glass was pressed. Again the genius agreed and swappedd it for a third that had a perfect screen but also had two large nicks in the top chamfered edge. I kept it because the screen is what I cared for most, and who knows if the next phone I exchanged it for would have been okay.
I've had the same struggles with iPads. Until and unless Apple gets its quality control under control, I will continue doing what I do. Don't care what anyone else thinks.
But what if I think it's a great idea? care then