I just went to my local gamestop in Denmark, and their pre order bonus included, the steel case, a keychain of sackboy in GOW costume, costumes of all characters and the crossbuy vita version. Thus this inclues everything, I'm thinking that the Amazon inclues this aswell. Anyway, check your local gamestop if you are going to preorder outside of UK.
Amazon Co UK does not include the pre-order costumes only the steelbook (which I don't like). I was forced to buy the game on PSN.
Playstation God of War Stars Battle Bore y'all !!!