I have a katana, sai, and chucks from my martial arts days. The chucks would be pretty useless against anything that can't feel pain (rataan hurts like hell when it hits, but it doesn't have enough mass to do serious damage). The sai on the other hand are pretty brutal. The katana is a reproduction of the "Godsend" sword from Heroes, it's sharp stainless, but I doubt it'd hold up to much punishment. That said, it's got a long reach, so I'd start out with that until it failed, then go to the sai.