I bought a PC etc. from PC world some 3 years ago and had trouble with the screen during the first year and this was replaced like for like.....all OK.
During the second year when the manufacturers guarantee had run out and I had the same problem again, this time it had to be replaced under the extra guarantee I had been enticed into taking out on the whole equipment. Oh boy was this a different story. They sent
ABSOLUTE RUBBISH and when I queried this they said they had replaced like with like. Nonsense!! I am a person who does not take these things lying down and I had a huge battle with them bringing into the dispute the manager of the shop where I had bought the equipment and he refused to help until I told him that his shop was the retailer who had sold this to me and was dulty bound to help!!!!!!! After many more telephone calls, they eventually capitulated and sent me a larger and better screen.
After this episode, I would never take take out extra guarantee on any of their products ever again and even their employees quietly agree with me!!!!
My theory on buying is select the item you would best like, then shop around for prices on that item and buy without extra guarantee.