I have all five books. I've read them cover to cover about three or four times. I've also used them as reference material.
When they first came out, they were pretty advanced as martial arts books go...They had more theories and concepts with more analogies and examples than anything else. The technique breakdowns were (and still are) the most detailed ever.
Now when I reread these books, I see that Mr. Parker was truly a genious. But, he was a genious in need of an editor. To me, the material seems to ramble. Some of the concepts seem to be a little thin in real world application (Black Dot / White Dot is my un-favorite). Many of the concepts are explained in a round-about way making it difficult for the uninitiated to grasp. And, In light of current publishing standards, the illustrations are crude and the photographs primitive.
I think it would be great if a professional author (maybe Tom Bleeker?) collaborated with a few Kenpo Seniors on an update. A revised and updated Infinite Insights with tighter writing, newer illustrations, and clear color photos in a large format would certainly be the best martial arts book series available for the forseeable future.