I've trashed campy and d.a. headsets (once via bad wrenching/hard riding, once via 'deferred maintenance') I've never trashed a King. (and that's not to say I haven't tried!) Not only that, but I know that if I do manage to destroy the king, they'll make it work again at a super-generous price, regardless of the fact that it will have been entirely my fault.
There is a very short list of companies that stand behind their products unequivocally, and Chris King is near the top of that list.