Installed a factor 55 prolink the other day. While I was at it I went to install a new winch control box as we had a brand new one at the shop that had a damaged cover. Since the new cover was damaged I needed to reuse my old one. During that process 3 of the new solenoid studs broke and 3 of the old ones broke. So one trip to quadratec later I'm several bucks lighter to "fix" something that worked perfectly fine. Moral of the story: if it ain't broke...
Feel your pain, I try to stick with the, "it's Broke, Upgrade!"
I think the only real long term fix is new headlight housings. It seems like after you polish them your committed to doing it 2-3 times a year.
See I feel with the off the shelf stuff its designed that way, you can take my process one step further by doing a clear coat of pain, and then wet sanding and buffing, and that will get them to last even longer.
Right now this is a test to see how long it will last like this without any wax on them (didn't have any at the time I did this) and go from there, the Camry headlights will definitely need to be replaced soon due to them being the cheap ebay ones.