The Borderlands 2 Loot Chest is £100 here, and this is £160, so an extra £60 is quite a lot in the UK, compared to just an extra $30 for you guys.
The 299% RRP thing you are getting at, I'm guessing that was from a wanted post? Where somebody said they'd like one as long as it's not for 300% the RRP, he suggested 299% as a joke. (That is, if I remember the thread correctly).
I also agree that the price of this is ridiculous, but I've got one preordered anyway
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