First post, but a very good one in my humble opinion.
These were in a sales basket priced at £19.97. However there was a sign above the basket stating that everything in it was half the marked price. This was confirmed by the sales assistant and I can confirm it myself as I purchased a copy. It is probably store specific, my Xbox 360 copy was found in the Hanley Potteries Centre branch. There was at least 2 copies of each format and I have a receipt which I will scan and post if requested.