I don't want to be that guy, but "Don't drop your knife" tends to be one of those things you got to learn to do to handle knives. Otherwise getting one of those knives that don't flip open with a light tap are more expensive than the surgery it takes to close the wound from getting slashed by one of those knives. So something around $500. I got a couple of blades myself, though I'll be honest when I say I like my knives that are easy to whip out at a moment's notice. Cheap, sure, but stab wounds from a $40 or a $200 switch blade aren't really different.