Modern day auto finishes dont need any kind of protection. Their chemical make-up does everything necessary to protect against the elements. We use DuPont system at work, but I have also used , and am certified for PPG finishing system. I've used BASF and Sikkens also. They all guarantee their finishes not to haze out or fade, guaranteed gloss retention and color brilliance retention, for the entire life span of the finish. A wax or " clear coat protectant " will do nothing to help this . A wax is good for other reasons . It will make it easier to clean road grime , tar , bugs , etc. A good wax job will help out on an older vehicle, maybe 2000 and older, as these vehicles had lesser quality finishes on them. As with everything else, paint systems have been improved dramatically over the years, especially in the past decade. They now have " self-healing clears " that will "melt" scratches away on their own. The water-borne systems that are coming on-line are impervious to oil based solvents. This means that you can use a mineral spirits or thinner to remove tar and spray paint without harming the clear. Most sales pitches at the dealer are just that, sales pitches.