A lot depends on how handy you are and how you feel about fixing issues when, not if, they happen. And of course the price of the extended warranty, the coverage, and the length of the warranty. And the issue of coverage is a real sticking point. What you consider a covered issue, may not be considered a covered issue by the warranty people. Just remember the insurance company doesn't make any money by paying out on claims.
We got an aftermarket warranty for our truck when we bought it. I have never bought one, but Peggy insisted, and said she would pay for it. As fate would have it the air conditioner condenser went out and was covered under the warranty. But the cost of the warranty and the cost of the repair were very nearly the same amount. We had no other repairs required before the warranty ran out, so basically it was a wash overall.
Personally I'd save my money and give it a pass.