Ok, so I have a friend that expecting to be deployed soon. I am lookinf for some advice on a folding knife to give him before he leaves. Something that can take a beating, holds an edge good, easy to put the edge back when it's needed, and around a 4" blade. Around $100-$150 maybe a little more for the right blade. Any and all advice will help. I'm not a huge knife expert but I'm really trying to learn more about them.