If you're an experienced martial artist, then you know that there's a lot of bad instructors out there, who are either bad martial artists, bad teachers, or both. However the instructors at Berkeley Krav Maga are easily some of the highest caliber martial artists you will find, and will probably be among the best teachers you will have had in your life. For instance, a person may talk about how skilled they are (and may be truly skilled), but if they can't pass that knowledge on to you, then you should probably move on. If you want to learn golf you don't go to Tiger Woods, you go to Tiger Woods' coach. If you want to learn Krav Maga, you go to Danny Zelig (head instructor there). There's something special about a teacher who greets each one of his students by name and then proceeds train them to elbow people in the throat.
Pros: Amazing training, friendly and skilled teachers, newbie friendly, no egos, great value
Cons: they don't have locations all around the world