How to stop new headlights from fogging

Looking to get new headlights but the ones I'm looking at seem to be prone to letting in moisture and fogging up. What can I do to keep out moisture and keep the lenses clear?

 

Either split them And reseal with butyl rubber, or run some silicone around the outside of seal. And to protect the lens, you could either use something like aerospace spray protectant, or put a laminate film over them. Or just plastx headlight buffer, and buff them every so often. I am using plastx myself on my current lights once they start to haze/yellow here in az. But whenever in get around to doing my next retro with new housings (spyder, which is similar in quality to anzo) I will probably put laminx film on them.

 

Yeah I live in AZ too, sun kills everything. Do you know of any better quality headlights like the ones I'm looking at??

 

I've heard depo are better. Not sure where to get em though. Rockauto I think.