Are you guys talking about martial arts? If so, mixed martial arts is the best overall (in my experience). Good for getting fit, very practical. It takes the best bits from all the styles, and though some people poo-poo it for that, it really is very good. Tae Kwon Do was a lot of fun also, good for fitness, but not very practical. Karate is more practical than TKD but a lot of styles still focus more on tradition than practicality. Kung Fu I haven't done much of, but from what I've tried it was mostly very close quarters stuff, incredibly practical but also more spiritual than the other styles I've tried. My father has been doing Kung fu for years, and using it has beaten several higher ups in other styles, if that says anything.
Thanks
Yes, I think its worth it. Though there's no hurt in waiting to see if it gets cheaper I guess.