People that own an iPhone 5...

Hello. For years, I lived without a phone and only with a PC and an iPod touch (I was between 11 and 14) and then I got my first smartphone; the Galaxy Nexus. I loved it. A year later, I got a Nexus 4, and loved it for a while, but after a friend getting an iPhone 5S, I began to fall in love. Not with him though, the phone.

I had left iOS on the iPod touch when iOS 5 was on the go. I've used iOS 7 in an Apple Store and I love it. But, I used it on an iPhone 5C.

Now, I know the 5C and the 5 have essentially the same specs (nearly exactly the same), but since the 5 is no longer available new, I would have to get a pre-owned one. I may decide to get a 5C, but if I did decide to get a 5, my main concern would be battery life / performance; not because of its specs, but, from my understanding, these things deteriorate over time.

So, main question being for those with an iPhone 5, has your battery life / performance deteriorated over time significantly? Also, any general tips about either getting a 5C or 5?