Dull Headlamps

Hey guys... need some help here. I've got a 96 Civic EX, and maybe some of you have this same problem...
The headlight covers are really, REALLY dull. Anybody know of a way to get them back to looking new, like, really clear and bright. I've used plastic cleaner, and rubbing compound, after a recommendation from a shop... do these really work? I've seen no big improvement, maybe I'm not patient enough.
Hope you guys have some tips!