Check the website and other reviews, like Google. Mixed as far as I can see, and some may be fakes so who really knows?
FWIW, these things are insurance policies, and no insurance company can survive by paying out more in claims than they take in in premiums. You'll probably get more responses, but in general, I think it's better to save the X-Warranty premiums, put them in an investment account to earn some interest/dividends, and use that money to do any future repairs as necessary. Just my opinion.