There are too many variables to give you a reliable answer. Everything depends upon the integrity and reliability of the company underwriting the warranty, what is covered under the warranty, what (if any) deductibles you need to pay, whether they pay the repair facility directly (or simply reimburse you later), and what repair shops will accept their coverage.
I have been looking for an extended warranty companies and I found out there more than 500 companies in the States out of which about 20 are accredited or I would say reliable. Here is a link that can help be choose a good company and keeps you away from scamers.. http://www.vpanet.org/Certified-Companies
You may want to search for the company in bbb.org_nr_
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