My iPhone 4 had good contrast, 4s was noticeably worse. iPhone 5 is perfect and I'm afraid that 5s will be worse. I'm not getting in the screen cooler vs warmer debate here, I just want letters to be black and sharp. I'm with AT&T but I wonder if I should order from apple (store?) to make exchange easier if necessary. I think that screens vary from one OEM to another and even from one batch to another.