I paid a local clear bra installer $100 to restore my pretty scratched up and oxidized headlights AND put on a clear bra on the headlights for a permanent fix.
As some have mentioned, when you use most of the headlight restorer kits (probably 95% of the kits out there), work great to remove oxidation, hazing, and scratches but that process also takes off the UV protectant on the lens. Most of these kits do not come with a permanent sealant. Without apply a permanent sealant over the newly cleaned headlight, you're looking at re-oxidation and hazing again in 6-12 months.
Other than a permanent sealant (do note that even some "permanent" sealants aren't that permanent), clear bra application over the cleaned headlights is the way to go.
My installer used Xpel film, but this is also promising (if you're comfortable with some DIY work, which should be easy on the E70:
Lamin-x Protective Films : Headlight, Tail Light and Fog Light Protection
http://www.xpel.com/headlight-protection-kits/