If you’re not protecting your head with a reasonable helmet, you’re either pushing a cave that’s deeply, horribly tight or else you need to think about just how squishy the human brain really is. Also they’re a pretty convenient platform for mounting your primary light. Despite a lot of internet rant, the best helmet is… the one that fits you comfortably. There never was a ‘best helmet ever made’. However, if you find that helmets slip on your head, or sweat gets in your eyes, consider wearing a buff or helmet liner; they can work wonders.