This is a good series of DVDs. It does start from the very beginning, so some of it is very basic punching, kicking, and blocking. But then it moves into some much more advanced techniques, including grappling and weapons. So, it does indeed seem to cover the range of skill levels that it claims to, from yellow to black belt. The techniques seem very reasonable (I hold a black belt in Goju Ryu myself).
The production quality is fine. No bells and whistles, but everything is well lit with a nice, clean, light-colored background in the studio (which helps the visual presentation) and things are shown from a variety of angles.
A number of reviewers have commented on Mr. Cohen's accent. While it is thick, I had no trouble understanding what he was saying. So no problem there.
Mr. Cohen does often blow through some combinations very quickly (too quickly I think). The rewind button on my DVD player got a good workout from me going back several times to figure out what he just did. The DVDs would have been better if more time was taken to break the techniques down in more detail. He does explain what he's doing most of the time, but doesn't really go into the finer details of it. And there were some techniques that he threw in from time to time without ever explaining what they were.
If you have other martial arts training, you can probably follow what he's doing without much difficulty. But if you're a brand new beginner, I think you'll need more explanation of what's going on.
And definitely don't try some of these things at home without additional explanation because some of the moves are quite dangerous. There are some head cranks in there (twisting the head violently to break the neck), a number of joint locks, and some gun disarms.
On the gun disarms, I didn't hear much about gun safety on the DVDs, which concerned me a bit. (I've done some competitive pistol shooting.) Although he was obviously using a dummy gun on the DVDs, he didn't really explain that before jumping into the techniques (NEVER, NEVER do this sort of stuff with a real gun, even if you think it's unloaded). And in executing some of these techniques he didn't really explain the risks of what happens when (not if) the gun goes off in real life (you can't crank a gun around to the side with your opponent's finger on the trigger and expect that it won't go off while trying to wrench it from their hand...even if you don't get hit with the bullet, you're not likely to maintain a grip on the top of a semi-auto when the slide cycles).
I give the series three stars because on the positive side, Mr. Cohen covers a lot of ground and there's a lot of good information there. Because I have other martial arts background, I felt like the series gave me a good orientation into Krav Maga. On the negative side, the verbal explanations of the techniques could have been more thorough, particularly for that part of the audience with no prior background, and particularly for those techniques where inexperienced partners training at home could really hurt themselves or each other without further explanation.
As a side note, I have to say that as the series went on I was feeling more and more sorry for Mr. Cohen's assistant who was the recipient of much of the mayhem in the DVDs. Although Mr. Cohen was obviously pulling his punches in the demos, he was often making at least light contact, and his assistant seemed to get up off the floor a little more slowly after each time.