Hi
When I got my teg, the headlights fogged up something bad. However, because I drive with my headlights on during the day and then obviously with full beam on and off during the night when needed, the fogging in the lenses just went over time from having the lights on. I've also been told by a company that fit the Lexus style rear lights to cars that the way they stop those lights from notoriously fogging up is by drilling the smallest of pinholes in the bottom of the lense - underneath the visual face of it. This stops the fogging up also apparently.