This contains 4 hour-long programs (each one's actually 52min. since there aren't any commercials). Anyhow, that's about 3 1/2 hours for 10 bucks.
The documentaries are each very good -- some of them are a little densely-packed, so you may find yourself rewinding a few times to catch everything. Although there are some interviews and the requisite pan across a photo while the narrator tells the story with the stirring (or foreboding) music, these documentaries consist mostly of wartime footage (which is good, you didn't pay your money to spend the time staring at a map). They are very well done, with a lot of good information. Narration, writing, and editing all come together to make a comprehensive and informative product.
Lastly, picture quality and sound are decent, even with the wartime footage (sound effects added later, of course). Highly recommended.