Thought some of you might like a read of the Martin Lewis report
http://www.moneysavingexpert.com/news/shopping/2011/04/tesco-weakens-price-check-guarantee-again
You can't be Asda on their cafe prices. I pointed out they charged me 40p too much on the meal deal and they wrote off the complete bill for two roast dinners, coffee and slices of choccy cake saved me £14.