Actually, the official guide does have some interesting lore bits, and was written by the game's lead designer.
But would it be worth purchasing for that much to you? You have to be a big fan to spend that kind of money on this. Don't get me wrong, I'm a fan (I'm not active on other forums of games that I like), but my money is definitely better spent somewhere else. Hell, I could almost buy a car (yes, a very crappy one) with that kind of money.