I've been doing detailing for years. These "coatings" are just the flavor of the week. Nothing that is applied in this manner will provide a shield to protect the paint from impact and abrasions. All of these products are designed to "optically" improve the surface. They protect it by making it harder for surface contaminants to stick on the surface. The slicker the surface, the easier it is to clean, and the less likely that you will get any contaminants to etch into the paint.
Waxes and polishes have been doing this for years. Polish is the best optical enhancer out there, but it is not durable at all. It requires a wax to protect the optical enhancements. Waxes vary in durability, but for the most part, they should be reapplied every month or two. Waxes and polishes also have nutrients that are very important to the paint which needs to oils to stay "alive". The more sun that the paint is exposed to, and the higher the temperature, the more often this needs to be reapplied.
These coatings that everyone is talking about still have to be reapplied, and the "paint correction" involved is the same process that is needed for a top quality shine from a wax. If you just apply wax, it will bead water, but the finish won't be as shiny as you could get. The coating folks are making their money on the correction end of the detail process which is invaluable for the best appearance. The actual coating that is put on, is just another version of wax when it all boils down.
I've seen the amount of money that is charged for these coatings. I'll stick with my Meguiar's process which can be done in about a half day....