I had a SGS3 for a while, nice, but slightly clumsy oversized screen, a downgrade in handling from the SGS2 (which I still have).
My biggest problem with the SGS3 is the feeling and look that it's made from recycled ice cream tubs. Horrible, cheap, shiny plastic.
The iPhone 5 looks better, handles better, and functions better (as many have said, multiple widgets end up annoying, I ended up with one clock widget and 8 icons on the Android home screen), Android needs tweaking and rooting and messing about with to get it to work properly.
Perhaps I was lucky, I have a blemish free iPhone 5, it has excellent battery life, wifi, and signal (better than my iPhone 4, or the SGS3), it is fast, smooth, and just works as it should.
I don't think I could have a better phone than the iPhone 5, well, perhaps a jailbroken iPhone 5 would be the only thing better I can think of

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