The best fighter is not a Boxer, Karate or Judo man. The best fighter is someone who can adapt on any style. He kicks too good for a Boxer, throws too good for a Karate man, and punches too good for a Judo man.
When people talk about fighting schools they say that Kung Fu, or Karate, or this other style is the best. That is silly, and the problem becomes that the fighting style then becomes set in stone with no growth, and no adaptation, because what works well with me might not work for you.