Any martial art style will work, it may not work the way you train in the dojang (dojo) and it's not suppost to, the dojang is where you practice different drills and sharpen skills, for that time you need to defend yourself or family, self-defense is an instinctive reaction to an attack by armed or un-armed attakers. And it's really up the the student he/she trains hard and pushes themselves right to the edge, the instructor can guide you but you have to make you, and that the way it's always been.
Ken
Ken