In this one respect at least, Sue and I have had a lucky year.
Last summer, our air conditioner broke down on a very hot day. The service people came that night; it turned out to be the compressor. It was replaced at no charge, including what would have been a horrendous off-hours service charge. Why? Because we had purchased the extended warranty almost ten years previously. The compressor broke down just in time for us to reap the benefit of that purchase and should be good for another ten years.
This summer the AC system also broke down on a similarly hot day, and the problem was found to be in the furnace with the fan not turning. It turned out that the $1000 computer control board for the furnace had given up the ghost due to a power outage just the day before. This was a problem with this model; usually the board would short-out within a year or so, but ours lasted for many years, fortunately frying before the extended warranty was up rather than a year later because it was bound to happen. The extended warranty more than paid for itself. (Note: we now have the new and improved 3rd generation model of that control board, which is not so susceptible to breakdowns from power outages.)
A few weeks later, the emissions warning light in the car came on. I would tighten the gas cap, and it would go off ... for a while anyway. Then, I bought a new gas cap, which didn't help. So, we took it into the dealer who discovered that it was the catalytic converter that had run afoul. The assessment alone would have cost $120, the part $1200, and who knows about the extra hardware required as well as the labour to replace the part. We beat the extended warranty deadline by 4 months. Phew! Once again, the cost of the warranty more than paid for itself.
For minor items or even modestly major items such as my newish camera or lens and such, I usually don't bother. Based on my experience with cameras, I take my chance on it lasting for at least three years rather than forking out $300 for a 3 year warranty, but it has worked out in these three big ticket instances. In these cases, it turned out to be a good thing that we worked the extra cost of the extended warranty into the purchase price rather than having to find the emergency funds, particularly twice this summer, when other expenses are ripping our wallet apart.
But let us hope that we can catch a break from these breakdowns as I am getting nervous.