I have never bought an extended warranty in my life.
Either it works out of the box, or it doesn't. Extended warrantees were invented for the sole purpose of generating another income source for the dealers.
I have never had a product, vehicle or otherwise where an extended warranty would have benefitted me. Defects show up very quickly, read under manufacturers warranty or the product performs well past the warranty period. What is your come back when the dealer says, "sorry but that isn't covered".
If you are going to lose sleep over it, then buy the warranty otherwise keep your money in your jeans.
I figure I'm ahead by maybe $10K from the money I have saved, so I still say no thank you to extended warrantees.