id say haidong gumdo, thats what i would join...i have been learning haidong gumdo for about a year, and my masters friend came one class and taught us some kendo....they are a lot alike but, kendo doesnt have belts like haidong gumdo, in kendo when u block u dont move the handle of ur sword, and that was very confusing to me hehe.... in haidong gumdo when u block u move the whole sword, in kendo, if i remember right, there are no forms its just pure swordfighting practice and basic stuff.....i dont know of any other differences....so cya