I've had my white 5C for a day now and absolutely LOVE it. I played with a few in shops, but it's obviously not the same. I had a few second thoughts about getting the white and thought I should have gone for green or yellow, but I love the white and the way it goes with everything, especially all my other Apple kit whether it's white, silver or black.
I honestly prefer the feel of it to a 5/5S with the smooth edges too. The plastic almost feels like ceramic, but without the coldness. When I hold it and my S3 at the same time, the S3 feels like a cheap toy. I think that's mainly because of the weight though. Personally I prefer my phone to have a bit of heft to it.
Another big difference coming from the S3 is the screen size obviously. It is noticeable, especially when watching TV, sports, etc but it's not too small. I couldn't go back to 3.5" now though, that's just teeny. I remember Jonny Ive talking about how 4" was best for using it with one hand. I called BS at the time, but might just eat my hat now. I have big hands, but tended to use the S3 with two as, although I could manage with one it wasn't comfortable. I knows it's OS related, but hated the keyboard on the S3 (either Samsung or Android) and found it really inaccurate, even in landscape. I could barely get a single word right first go. With the 5C I can use it in portrait with no problems.
It's all very personal, but I love the 5C. It may not be as premium as the 5S, but it is a premium phone to me. It is really nice to have something different from the norm as well. Not that I'm an attention whore (far from it), but nearly everyone I work with has an iPhone and a few have got a 5S already, but no one batted an eye when they pull them out, but nearly everyone wanted to see my 5C (I'm going naked btw). It certainly got a lot of "Oooooo's".
