Like pretty much everything else in life...it's 'worth' what someone is prepared to pay for it. True market value is based on supply and demand, how many of them are there, how many people want it, and how much are they willing to pay for it. If you think that your life isn't worth living unless you have bought absolutly everything Bon Jovi have ever released, even if that means buying the same music in 2 or 3 different formats, then your probably going to pay what the seller wants.

Me? Nope. I've already got all the music included in this "box set" so I wouldn't pay more than 20 quid for it. I would expect a ton of stuff that I don't have for that much money.