scratches

So I recently bought an SDS-100 scanner from E-bay. Unfortunately with no returns accepted. It was a decent price, but the previous owner seemed to have scratched up the display pretty bad and it wasn't properly showing in the low-res pictures. Most info is readable, but some parts are not. I...

Do you any of you use screen protectors on the handheld units? How durable are these screens from scratches and dings? Any experiences? I bought a used pro-164 that has some dings on the display area and such, and am wondering how to stop it from getting worse. I will be putting the...