Go in store. They keep a separate stock for exchanges.
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I would have sold that thing so fast!
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Called ahead to the Sprint store and none in stock, yesterday they had (2) tough. Buttttttttt I went to the Apple Store and got a replacement real quick after waiting 1:40 hours for my reservation. I checked ALL the 5S's in the Demo tables and none had a screen popup issue and they are used ALOT (Millenia Mall Apple Store) busiest tourist store in Florida.
I saw the Apple cover and I like it but didnt had $40 to spent at the moment lol.
In front of me was this tourist lady from Brazil or Venezuela in her 30's buying 10 ipads, and 8 iphone 5c, sexy as hell, and a guy behind me was from latin america also and offered me $2500 for my iphone 5S 64gb, I said no ofcourse lol, I run my business with my phone, but the temptation was there.
I would have sold that thing so fast!