Got my white grip cover today and it's much better than I expected it to be.
Looks: It looks and feels phenomenal, hardly adds any bulk to the phone and provides protection too. The feel is similar to how my new One X felt. The back has a very nice soft feel to it, different from both back shells and flip covers.
Fit: Fits perfectly. Zero creaks or noises. Mind you, it doesn't click when you put it on. It's held there by the bumper around it. But the fit is very reassuring.
Protection: The back is much harder than the standard back plate, thus providing better protection. The bumper around it also feels decently protective. Buttons are still nice and clicky. Cutouts are prefect.
Worth every penny. Will be buying the blue one soon too! Go for it.