Wait you have a iphone 5 and you want to get 5s... but can't wait to play with 5s so you will get 5c, until 5s become available.
Besides the color and the plastic back of 5c, is Iphone 5 and 5c technically the same. So you don't need to get a 5c, because you already have a iphone 5 that you can play with.
What do you want to play with your 5c?
-It does not have a Touch ID
-Camera doest not have two tone flash
-Processor is the same with your iphone 5
-Camera does not have burst mode.
-M7 is not even included in 5c
Unless you have fetish with Plastic with colors.
More than that, you won't notice the A7/M7/64-bit stuff one bit at first. It'll take some better photos, and touch-ID is nice. No real toys to play with on the 5S over the 5 either for very long.
I think OP just wants to drive to Apple store, buy something, unbox it, and return it.