I think coatings are a bit over rated. Yes they have somewhat better durability than other methods of protecting paint (I can get almost a year out of a $10 bottle of DG 105), but in my opinion protection (or lack thereof) is not what causes paint to get all messed up.
It's scratches and swirls and I have yet to see anybody prove that a coating helps to prevent the very thing that causes all the headaches in the first place. Nobody polishes paint because their wax only lasts a month. They polish paint to remove defects caused by poor washing and drying techniques primarily. :iagree:
I've used several coatings and they scratch just as easy as non coatings do. So for me the only reason I see to use them is because it saves time by not needing to have to apply a wax or sealant more than once a year.
However unless you figure out how to prevent the scratches and swirls that are usually self induced a coating is a waste of money because you will be polishing it off long before it needs to be replaced.