I have an iPhone 4S, I would honestly wait for an iPhone 6 (larger/wider screen), rather then being eligible for an upgrade and having a taller(compared to the 4S) with beefed up specs(compared to the iPhone 5) iPhone 5S.
I don't use my iPhone to masturbate or text and drive, so I usually have two hands available if I need. What's the infatuation with having to do every single function with one hand anyway?