Otterbox. These guys do it right.
I bought a new case for my iPhone. My fat fingers and some dust got under the screen protector they provided...and I dreaded the prospect of asking for a replacement.
Surprisingly I found their toll free number prominently displayed on the web site.
After a remarkably few (3-4) prompts...Deb answered the phone (cheerfully & on the first ring), and offered to send me two new screens. Granted the replacement screens are not expensive...but the quality of their personnel and training isn't.
I’m a customer for life.
An Example of Really Great Customer Service