It depends what you're looking for, if you're looking to be able to fight properly then I agree with the others that they are probably useless and boxing, MMA, etc. are probably what you should go for.
However if you just want to get fit and hone your skills and mind then go for either, just pick one that you think you'd enjoy! Even if you try it, don't like it, and then switch to a different one that's fine.