Wax / Sealants are made to protect the paint surface from contaminants and oxidation. It will not protect the front end's red zones from rock chips regardless of how much or which type of wax is applied. It is true that the bumper could be repainted for $300-$400 from a professional body shop, but that is only the cost of repainting the bumper. There is also the headlights, front portion of the hood, and mirrors that are all prone to rock chips since these areas are all facing forward. Painting these areas especially the hood will cost another $300-$400. There is also the cars's downtime at the bodyshop.........between 2-3 days if they're quick at it. There is also the possibility that the paint won't match as well as the stock paint. Once these areas are sprayed new paint, this is actually the most vulnerable time period for paint as it is still soft. It will take 30-60 days before the paint is fully cured, which means chipping is even more likely right after the front end is repainted.
There is quite a lot of negative press on clearbras because of the film fading and yellowing. Most of these came from 3M's old films, which is very visible on the car due to its orange peel effect. Today's film by Venture, Llumar, and Madico are all ultra-clear and does not have any orange peel whatsoever. Even on dark colored vehicles, the clearbras for the above mentioned companies are not visible. Venture's film along w/ the other two are transparent, and does not alter the aesthetics of the vehicle and is virtually invisible. The purpose of urethane manufacturers such as Venture is to provide high-end vehicles with paint protection that is invisible and is easy to maintain - just wash and wax it as if it's not there. Plus, there's a lifetime warranty from bubbling, cracking, yellowing, and fading. Here are some pics to show how clear this film is: