Couple of factors to consider: Is he a babyface? Or could he easily pass for a youthful 25-30 yr old? Also, what are you planning on doing and where will you be doing it?
I think it's a really cool idea! I still have two more years before my oldest son will be "eligible" to OC, so you bringing this topic up kinda gives me a few ideas. Prospecting, camping, etc. We can safely OC and not have the hassle factor.