I've heard several times that something called "liquid glass" is good, but I've never been able to find it. however, I recently found a bottle of it and the pre-cleaner in an auto store. I was curious about just how well it worked and how hard it was to put on. Also, can it be used on the polished rims and plastic trim? I just want something that will make my black pr5 look really nice. any help is greatly appreciated.