Just my own opinion....
- If the extended service was from anyone other than the manufacturer themself, I would not buy it. I've heard too many horry stories of people trying to collect on third party contracts.
- Even if it is from the manufacturer, I never buy them. If it's a good deal for me, then the product is a piece of crap. If it's good deal for the manufacturer, then it's not a good deal for me. These contracts are a great source of revenue and profit for manufacturers, retailers, and whoever else sells it to you. That profit comes out of your pocket.