I replaced the OEM projector housings with some ebay special black OEM looking projector housings. My OEM headlight housings are very pitted and faded and wouldn't stay polished even with a clear coat. The ebay specials look just like the OEM headlights, except painted black. Unfortunately, the light output, cutoff, and aim were nowhere close to OEM with the OEM halogen bulbs. Terrible, uneven and distorted cutoff and a very pronounced rainbow effect at the top of the cutoff. The actual light output sucked as well but I put up with it for a year or two. I even purchased some used OEM housings that were better than mine, that I had intentions of polishing and swapping out the ebay housings.
Somewhere along the way, I picked up a set of VLed LED bulbs and figured I'd try them because it couldn't get much worse. Much to my surprise after a little adjusting, the LEDs drastically improved the cutoff, aim, and definitely the actual light output. They also got rid of that crazy rainbow effect that was going on and I was able to aim the lights correctly. No hot spots and they don't blind oncoming traffic. After about 6 or 7 years in the hot NM sun, these ebay headlights are starting to fade and the black paint inside is pealing so eventually I'll replace them. Hopefully I can still get the same ebay headlights!
I was so impressed with the LEDs on my 4th gen that I ordered a set of LEDs for my 5th gen but other than updating the look of the light output, I would say overall they are no better than what was originally in there. The projector on the 5th gen is totally different and it took a lot of trial and error to get the LED to "clock" correctly so the overall light output is just OK.