I have never heard anyone say that a warranty is worth the money.
What I have heard, over and over again, is that its just something that helps settle the nerves of first time home owners and those who are buying at the max they can afford per month.
One was included in our first house- it was a total joke. The sheer number of exclusions makes it damn near useless. They will pay for a pipe to be replaced, but not the drywall and labor to patch the hole thats made.
Its like auto insurance in a way- if you have it and something bad happens that qualifies, then it was good to have. If you dont have anything happen, it was money wasted in retrospect.
The major difference between a home warranty and auto insurance is- If you have something happen to your home that isnt covered- its infuriating since you have spent money and still have to pay for the repair.
If one is included in a home sale- cool.
I couldnt imagine paying for a warranty though.