If you look you will find a manufacturing date inside the helmet. At least I have found them in every helmet that I have ever had. I believe that standard reasoning is that a helmet has a five year shelf life. I've gone into year six before, but that's the oldest I've ever run. You do have to be careful with closeouts sometimes because I once got a two year old helmet. Nearly half it's life was already done.
I'm not in the one minor scratch or tiny ding and it's done crowd. It's really the foam that saves you. Most think that it is the shell, but that is not true. Sure if the shell is really damaged then yes it's done. Damage to the paint in of little consequence.
My last helmet was killed by my bike. Over thanksgiving at Spangler I had the helmet on the end of the bars at camp. The wind blew my bike over on the helmet side and the end of the bars did a number on the foam upon impact. I wasn't sad as that helmet had just hit that five year expiration anyway.
I wanna go DOT Snell approved, black white or mostly some shade of blue for under 120$ Gear is all FOX, as if it matters. Preferably light and cool, size large, may be able to cram a med 
check into closeouts. i got my current shift helmet for 50 bucks cause i had 50 credit on RMATV. There is no reason to go buy a 400 dollar helmet. unless you are worried about features like vents comfyness or easy release straps kinda of stuff.
never once broke a visor in my life!
