I got no case on my Zr but a small screen protection only.
So far, after 8 months, I m thinking about to change the screen protection but the screen itself is fine.
I didn't use any case because I ve read too that it was supposed to be fully resistant and I only got one small scratch on the back but all the everyday small scratches tend to disappear..
So it s pretty good for me as I m living in a tropical country, I go often in small villages inside rainy forest...
You need to be careful but this phone is quite resistant.