Are you referring to the invisible shield full body protectors? I do not believe they are permanent. Nothing is truly permanent in this situation. They are not bad, but they are definitely expensive.
In my honest opinion, I do not prefer protectors that you must put on yourself. You can have them put it on for you, but it does take a little while to get all of the bubbles out, and even then a day or two later a small bubble or two or three may appear. I prefer a full body case such as the otterbox. Yes it's somewhat bulky, but all I want is protection. I don't mind the bulkiness.