hey so what i did was wetsanded and polished them up till they were sparkling...
looks very good, every week when i wash my car i put more polish/wax on to keep them looking good
once you wet-sand obviously you take the protective UV coating off and now ur lights can turn yellowish if you don't maintain them properly (hence my regular polishing/waxing)
i am probably going to get clear vinyl and put it on top of the lens to make sure that they dont start yellowing, protect a bit against stone chips etc
BTW: my lights looked exactly like that when i did em
to start off... buy plastx polish, and try using it without wetsanding and all that jazz
if you like the result, sweet, if not, just wetsand
OH, and make sure to take painters tape and tape off the area around your headlights, i put fine scratches on my bumper under the headlights while wetsanding