I have only just received the book and already I'm disappointed. I bought the book as a reference work, not for any freebie "BOGOF" offers, and on that score it looks as close as an original reference work is likely to be.
However, I take great exception to a big banner across the front of any product which says "Free xxx" and that's the only reference to it in the entire product. No further info, no indication of a code or key or website to enter it. Just a scam, a pointless disappointing scam.
Hence one star. Book might be OK, but the cover has really upset me, please someone tell these guys to stop doing it!