I thought the guide wasn't bad, and prices, well, any car's worth what someone's willing to pay.
As it is, I have no desire to own a concours car, and if I did, I'd just ruin it by using it, as a car. There are still lots of cheaper P6s about, but the constant discussion about prices is giving people daft ideas about values. As it is, I can't afford to buy another P6, for a long time. The increase in prices is fine for people coming from boring classics that get trotted to shows and back, but not so good for people who buy the cars to own and enjoy driving. Me, I'll wait for the next big market crash.