I built an entire cab w/o the Project Arcade book, but I decided to buy the book for my next cab. I know most of what's in it, but I consider it a good buy for $20, since it's nice to have it all in one spot. I particulalry liked the chapters on stuff that alot of people here take for granted - like Encoders, and how to power up/down a cab with a key and bitstrip.
-T