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Now that you've sold it, buy another iPhone 5 32 GB. Pocket the extra money. The 5s isn't a big jump. I'm using one. If you REALLY want touch id (you don't), then get it.
 
Speed difference is just about the worse reason for upgrading to the 5s, as the 5 is already fast enough. Try fingerprint unlocking, which is actually more useful than Siri (the defining feature of the 4S), at least for me.

Siri was vastly overrated. I don't like having passcode on my iPhone in the first place. Fingerprint unlocking isn't worth it. Another gimmick feature.
 
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