The Grey Seal video is very much like the book. By the nature of the medium, it does make some of the concepts easier to grasp. For me personally, the video was great for learning, and the book is very handy to have for reference while actually building a puppet.
The Dave Privett video is great too. The pattern-making is really quite ingenious and very thorough. I'd call it a must-have for people who really know what the puppet must look like in advance, and are able to sketch those ideas. (As opposed, say, to the "Nip and Tuck" method from Grey Seal, which is more free-form.) It's not going to be a fast way to make a puppet, but it certainly is going to be accurate!
Really I like all three. Each has its own uniqueness, and they all reinforce one another too. Obviously there is going to be an amount of overlap in a few concepts, but even then each has its own take on technique. They'll only make you a better builder.