I looked at the Pinlock system--and their similar competitors--but 1) they don't make one to fit my helmet, and I don't feel like buying a new helmet to try it out; 2) It uses some kind of "fog absorbing" technology that has a limited life; and 3) Warnings about distortion and light refraction problems, esp. at night. Oh, and 4) It's expensive.
Well, I can't help with #1 because I did buy a Nolan specifically to get the Pinlock insert, the flip up, and the buckle instead of the prehistoric D-rings. At the time Nolan was the only helmet in the US that came stock with a Pinlock. I went on the internet and learned about them and went back and bought the helmet, since at the time the Fog City stuff was crap and I really wanted something better, and none of the wipe on/spray on stuff works more than a couple days.
#2 is total BS. None of my inserts have degraded in the about 5 years I've been using them. I've pulled them out of old scratched visors to put into new ones. I know they last at least a year and a half each. Now once I put one in a visor, I don't screw with it. I buy another visor for the summertime.
#3 has a little truth to it, but is still mostly BS. The only time I see any double image is in very very bright sunlight. At night, there's no problems. However, it saved my *** this winter, especially the past 2 weeks. I had total condensation fog around the insert, plus I had beads of water from my breath running down the visor, that's how humid & wet it was here in Florida. We had several days of socked-in fog in the morning. Without it my face would have been freezing with the visor up. I couldn't use the flip-down sun shield because it was totally fogged, but it shows the Pinlock was working.
#4... Wait a minute.... $30 is too expensive? Really?
I don't work for them, but they're one of the very few products these days that does just what it says on the tin.