I bought a Hakkotsu Iron Face lower face protection masks around October of 2010. Ive read reviews posted online and watched video reviews on youtube. If you're reading this, odds are...you've done the same thing as I have.
There's no doubt that the Hakkotsu Iron Face lower face protection holds up well against airsoft guns shooting 400 fps with .20g BBs. Video reviews would show that they hold up against 500+ FPS airsoft guns. The mask is definitely worthy of field use.
Here are my personal opinions about the mask however:
1. The mask is soft but sturdy. It'll conform to the side