Originally Posted by
USB
@Moonshake disagree with you on judo, i am judoka myself, but i would rather add judo to traditional MA. It is effective, but even the way you spar at judo is kinda nonstreet.
Me personally would recommend Sambo (i switched judo to sambo at one point), which is basically KGB version of judo, with punches and kicks. Also Sambo itself concentrated around effectiveness, not stylish throws, kicks or punches.
And of course the best defence from big guys are fast legs 
This is a fair point, and it also definitely depends on the judo gym itself -- like every gym, it entirely depends what is in the curriculum, e.g., if throws involving leg grips are still taught, how much ground game technique is taught, etc.
However, if I'm in an area where there's only karate gyms (where there's a high likelihood they're all "
black belt factories"), and a judo gym, I'm going to choose the judo gym.
Sambo is very interesting and worth mentioning too, although I will admit I don't know that much about it. However, I do know that a sambo gym will be much harder to find than everything else I've mentioned, unless you live in a post-soviet country of course.
If I'm not mistaken, yuki lives in Mozambique (according to his profile), and because they speak Portuguese, I'd say there is *some* hope in finding a Brazilian jiu-jitsu gym. Checking Wikipedia, Mozambique has also had competitors in Olympic judo since 2008, so I figure there must be a judo gym somewhere over there as well.