I tried Krav Maga as I have stated to earlier and loved it.
now for the disclaimer * i am not advocating krav maga is going to teach you to be a world champion fighter, if you were to box against a boxer, you will lose, if you try it against an mma fighter, you will lose. By learning krav you are not going to suddenly become a death touch warrior and will be able to take on 5 blokes at once. That happens only in movies.
So back on topic. I was never one who was going to hop into a ring to box or do mma but I love both aspects and a friend put me onto Krav as it was taylored towards self defense in the real world situations. It's a very evolving combat in that it doesn't have a certain style like karate, it just takes the best parts of everything and put's it into a real situation as best it can. Nut shots and eye gouging are very legal if you are trying to defend your own life. It teaches alot of MMA but teaches where it may or may not be beneficial. I agree BJJ is great and is very useful for taking on larger opponents, but rule number 1 in a street fight is never go to the ground, why? You can take 1 opponent to the ground but his 5 mates aren't going to sit around admiring your transitions, they'll more than likely stomp on your head, plus taking a bloke to the ground who has a knife in his hand takes the fight to a totally new dimension. Basically the aim of Krav is to do whatever it takes to get out of a situation safely and not to test your martial art skills. That is left for the ring.
But as I said earlier, if I were to box or do mma, I would lose but if the grub hiding around the corner wants to mug me, hopefully I know enough to give him painful balls and some blindness for awhile.