From my time living and traveling in the UK and Europe, I believe this type of insurance product is more mature/mainstream and has better regulation standards than it does in the U.S. Based solely on ads I see in the Tube and other mainstream places, it appears to be sold by major companies and commonly bought by millions of people. It's a big, mature market that I'd be somewhat apt to trust with my purchase.

But I too have never felt comfortable buying it based in the U.S. It's unclear to me which insurance regulator holds jurisdiction and how thorough that jurisdiction is about travel insurance products. All I see are horror stories about travel insurance that won't pay out. My own state's insurance commission doesn't even discuss it on their website.

If my main insurance provider (USAA) sold it, I'd probably buy it because I trust their other products. Even if Prudential or Allstate sold it, I'd consider buying it. But it's never those guys...it's always some third-party link off of an airline website or a different insurance-related site and it's not always easy to figure out where they're based, where my insurance rights are in force, how award travel is valued, etc.

I would probably trust Allianz for term life insurance. I trust Amex for credit cards. I trust Thomas Cook for...I don't know...the little books with train schedules in them? Not sure I trust any of them for travel cover...

Sort of like we Americans don't fully understand EU passenger rights, I think a lot of us wrinkle our noses when someone from outside the U.S. posts "Just buy travel insurance and this won't be a problem."