In my opinion, the First Recon Beret is one of the best helmets in the game, especially if you're going for a light armor build. Sure it doesn't increase your Damage Threshold, and the bonus to perception is good, but the real bonus is the increase to your critical chance hit. And according to the fallout wikia, I found out that you can actually wear them with Elite Riot Gear! This is due to the fact that it Elite Riot Gear is not marked as covering your hair. Not only will you get a bonus of extra perception, but a bonus increase to your critical hit chance! Just though I'd let everyone know.