They would never offer a warranty like that if they didn't plan on making money off it. That's how all "for sale" warranties work. So, if your Celi only requires an "average" number of repairs, you're losing money. The main benefit you get is protection against a possible major problem. Generally, I avoid "for sale" warranties because if you look at the broader picture, you can buy them for all sorts of things, especially home appliances. If you bought no warranties, you would on average do better because you have several appliances.
So, I wouldn't buy an extended warranty. If you do, you're basically buying peace of mind. Not necessarily a bad thing though.