The 5c is more or less the same as the 5, but in a cheaper casing. The 5s has new 64-bit chip, a new co-processor to offload lots of motion-sensing functionality, a much much better camera and the fingerprint sensor. Definitely not worth upgrading from the 5 to the 5c, and unless you're a keen early adopter there'd be no reason to upgrade from the 5 to 5s either.
True, but it's no good being first to market with something that never works! The jury's still out on Apple's efforts though, particularly if the stories about low yield rates on the new sensor are anything to go by.
Plan on doing that now...buying sim free phones rather than paying high prices on a contract....seems the best way to save money
If you're going to do it I suggest setting yourself up a Quidco account if you haven't already got one. There are always lots of sim only contract deals where they offer cashback.
Unfortunately i have already taken out an O2 12month contract for 21 pounds, i get unlimited minutes and texts and 1 gb data will look into it as the wife is going to go sim only soon