I had a 100,000v stunner I got to use in a potato gun ignition
Well, I was having a BBQ and some of the kids (early 20's like myself) got a bit toasted and found my stun gun loaded up with industrial Energizers...yes there is a difference! At first they just started sticking their fingers in it, then realizing that volts is nothing without real amperage, they proceeded to shock themselves over their entire bodies and actually takes turns passing the thing around. I finally had to take it away from them because I figured it probably wasnt healthy.
I got shocked once by some smartass playing with it, and it kinda feels like a bee sting, but that's about it. At that point I really wondered if they should be considered anything more than an overgrown potato gun lighter. Your attacker would basically have to have a hold of you already to use it, the switch is very small, you need to maintain constant contact for it to really start to hurt, and I think it would piss of an attacker even more than he already is. I know they make ones much bigger, but still, weak choice at best. I'd absolutely go with a knife over a stun gun.