I have come out ahead on extended warranties, mainly due to the pair of lemon PCs I got from Gateway. The first one I bought from them was so bad that I had a 4-page letter I sent them titled, "My Gateway Nightmare." They ended up replacing it with a better model for free. But that replacement, which I also had an extended warranty, had its share of problems which required several replacement hard drives and motherboards in the extended warranty period. This was back in 2003 when Gateway still had their local "country stores" so they recognized me coming in all the time. Eventually, the problems disappeared and the PC lasted until early 2012. I estimated I incurred about $800 in repairs while paying $175 for the extended warranty.
Another time in the 1990s, I bought a color TV which needed repairs under the extended warranty so I came out slightly ahead on that one.
So when I buy an extneded warranty on a costly item and I don't end up needing any repairs under it, I don't feel too bad.