I know the OP doesn't care for the latest and greatest but, OP, I would definitely consider putting up some extra coin for the 5. I think you will be much happier with the 5 compared to the 4S.
Don't get me wrong... I'm not burning 4S users - I think the 4S is still a beautiful, speedy phone and if you have one then I'm sure you are very happy with it.
I never had a 4S and so I could be wrong but a couple of my friends have said one of their favourite things about going from 4S -> 5 is going from 4/5 hours usage -> 7/8 hours usage in terms of battery life.
The more efficient A6 chip, coupled with a better calibrated + bigger display with a 16:9 aspect ratio seems like the iP5 would be well worth the extra cost over the 4S.
Oh, and let us not forget the other advantage that the iP5 has over the 4S.
You know what I'm talking about....
.... LTE