The Home Bargains chain of stores do bags of coffee for £1 and it tastes like it should. Make sure you get the right grade as there are 5 different strengths of coffee.
A reply for Jeza,as I can't see where to send a P.M. I have lived in Spain now for over 3 years and a "cortade grande en vasso" is wonderful, so now I have ventured into making stove top coffee, oh boy! that,s nearly as good.
allgram.
Most coffe shop coffee is not much more than hot water. I used to add a shot of esspresso but that doubls the cost. If you are talking about instant, my wife will drink nothing but Carte Noir. Every now and then there are special offers and we clear the shelves!
I heard that it is recommended that you change your coffee brand every 3 months as you get a bit bored with the same taste. Personally i love Nescafe original but will occasionally swap it for Carte noir or Gold