I have only had a regular plastic or bumper style case. I had one iPhone (3s) where the screen shattered after a drop -- but still worked due to the Zagg screen cover. My Applecare contract covered it, so all was good.
The new phones are supposed to be waterproof, so I am going to continue to go with the bumper case -- they are a lot cheaper and the phone is a lot less bulky to carry.
I have not done the Zagg screen cover since the iPhone 5 days... I'm a gambler
Just my