Not being able to find this game for £5 in any Sainsbury's I decided to go for Amazon.
A week ago I couldn't get free delivery on this even if it was stated in the description (I guess you need a minimum spend) but today it worked.
When voting, remember that you are not voting the game but the deal. If you don't like the game it's no a good reason to vote it cold.
Cheapest only in Sainsbury's... if you can find one.
PS: the PS3 version is £4.84 + £1.94 shipping, same thing