Upload & Sell: Off
Nikon ones are easy to scratch on the exterior, and allow dust to accumulate underneath the protector which may lead to blemishes on the actual display. The stick on GGS's look seamless, and the clip-ons are black to match the body better.
That's why I don't use the cover that comes with the camera. I go nude.
No scratches on the screen, the rest of my camera has seen better days. The screens are pretty tough. If I do ever scratch it, well, c'est la vie.