What's so good?
Well, they are less cumbersome than any other exercise system. By far. Even a pair of dumbells is twice as cumbersome, if you see what i mean. And they're no more dangerous than free weights are. You just have to consdier that it's technique. Learning to use them takes practice...Pavel, the main guy as far a kbs are concerned, says it's like learning a martial art. You can't just jump right in. It's significantly different than any other system.
It teaches the body to develop serious core strength. Vice grip, hard muscular torso, classic build large shoulders, powerful hips and waist (unlike body builders who have feminine waists, overlarge legs (unfit for fighting) and massive, unwieldy pecs.)