I carry a Honey Badger Ultratek (top one on the pic) in the front pocket strong side. Weak side front pocket is usually a Gryptillian or sometimes the Kershaw Speedsafe shown in the center in the pic below. In my back strong side pocket is a CRKT Ripple that took me a couple months of tweaking to get it to where it would open in complete silence. No "snick" sound when it opens.
What do I use them for? The way I view knives is they are strictly a defensive tool whose purpose is to get a threat off me or away from me. I do not view them as offensive weapons because I think staying around to engage in a knife fight is a losing proposition right from the start. Even if you prevail, the chance of serious injury is just too high.
I haven't taken a knife course per se, but I've taken a couple Krav Maga courses that included defending against a knife and using a knife in defense. Much of that technique involves other dynamics and focuses on very rapidly switching from defense to strong offense. Good stuff, but honestly if you aren't at the gym a couple times a week or more keeping those skills sharp, they're not of much use. For someone like me who doesn't have time to devote to it, it means I understand the basics but I really have no business relying on that as a good means of SD.
So, the way I see it is, a knife's purpose is to counter a threat by causing as much damage and making it hurt as much as possible for a potential attacker. That's one reason why I want my Ripple to open silently, because I don't want to advertise that an incoming punch or a grab to the throat is going to cost that person a good quantity of spilled blood and maybe, hopefully, give them pause to consider just how easy a target I am - or am not. I'm really not interested in going all Krav Maga on them to the point of their submission, I'm more interested in stalling them or opening distance that allows me to GTFO, because in a knife fight, that's where I want to be - away from it.
