i dunno what sorta dull/haze you're talking about, but on my corolla i have what looks like water marks all over my headlights, but they dont wash off... on the supra, my headlights were super cloudy and yellowing, and i used mothers plastic polish on them... they look brand new now. i was so impressed... im going to try the stuff on the corolla headlights right now, ill report back here with my findings in a few minutes...