A freind of mine has a khuk, and he says that it chops wood better than a small axe. when you hit the wood them you have to have people cleared out on both sides becuase those pieces are going in opposite directions with rapidity. another friend of mine has the 2 handed cold steel khuk, and it is a piece of crap from what I saw. check out Himalayan imports, they have good stuff from what I hear, and they have their own forum here. now, my understanding of a parang is that it chops better than a grass and brush machete, and so I would assume that it was more for jungle work where you need to be able to go through heavier branches. I am a total noobie, but that is my understanding.
BTW, don't go for the bear grylls if you want a good first impression. at least get a condor.