This book has a lot of great new cybernetic stuff in it (new classes, a gadget system for cybernetic attachments, new hardware,etc.), but it creates a system that doesn't mesh well with the original d20 Future chapter on cybernetics. I like my rules cut-and-dried and ready to go, but this supplement isn't readily compatable with the original d20 Future rules. If you want cybernetics to play a major role in your world you will definitely want to buy this supplement, but be prepared to make some decisions.