Tim,
I have this book and I think it really is worth the money. Things from the FARs, AIM, ACs, and ADs are explained clearly and simply. It doesn't feel as much like you are reading rules in lawyer language if you know what I mean.
I think that if a person were to know and understand what every single thing in the book meant, they would be completely prepared to fly for work on the technical, operational, and regulatory side of things.
The author, Richie Lengel, seems like a good guy, too. He even included his cell phone number on the letter that was in the book, though I haven't called it and don't know if it is a legitimate number that he uses every day.