The coating is a UV coating applied very thin at the factory (where the headlamps are assembled, not where the car was assembled). It'd be nearly impossible to get a good coating in the field (aka your garage). I do wish more options were available, though.
This is why once you clean/buff/abrade the lamps for the first time, you usually have to keep doing so forever: you actually abrade away this UV coating. There are some restoration kits with some type of glaze to apply, but it's very difficult to apply it evenly. Our Acura's lamps have been polished, and I usually hit them every 6-8 months, or whenever they need it. Our Honda's lamps have not been polished, and still look new.
I do park the Honda facing northeast at work. This has to be better than the alternative (southwest). The Acura pretty much stays in the garage during the day, except when my wife is out with it. But it lived much of its early life with my folks in the desert southwest.
This is why once you clean/buff/abrade the lamps for the first time, you usually have to keep doing so forever: you actually abrade away this UV coating. There are some restoration kits with some type of glaze to apply, but it's very difficult to apply it evenly. Our Acura's lamps have been polished, and I usually hit them every 6-8 months, or whenever they need it. Our Honda's lamps have not been polished, and still look new.
I do park the Honda facing northeast at work. This has to be better than the alternative (southwest). The Acura pretty much stays in the garage during the day, except when my wife is out with it. But it lived much of its early life with my folks in the desert southwest.