This is a gift for my mother, who isn't the most savvy iphone user, but loves the phone. My original thinking is that the 5c in white would suffice. But the refurb 5s also is somewhat enticing. She is not one to need the latest and greatest (She is upgrading from a a 3Gs). Is there a reason I should stray from my first thought of getting her the 5c? Thanks much.