Yup, Lamin-x is plastic, here's an amazon link: http://www.amazon.com/Lamin-x-S126Y-Fog-Light-Cover/dp/B00C6REQGO
As far as LED being better, it depends which LED you go with. The XML2s($120) for example output ~1400 lumens, stock lamps output ~500 lumens. Most LED kits out there output something around ~3-400 lumens.
I went with these. They say they fit a brz.... not true on my end. i still had to trim the vinyl slightly to make it work.
Just a yellow lamin-x vinyl cutout that goes over the lens. First thing I did to car actually, always loved the "jdm" yellow fog look especially on blue.