I'm an insurance agent of PruLife UK in Philippines and so far we don't have kind of issue regarding claims. All of my clients that undergo surgery or suffer illness that included in the policy they sign was paid promptly after a few weeks they file a claim. You should check the credibility of insurance company before you sign a policy contract and start paying your monthly premiums. Many fake/scam insurance company offering a too good to be true offer that always ending up on the story that you stated.
Insurance is an investement so better to invest on a well-known trusted insurance company!