Does Flex Seal really work?

I've been hearing a lot about Flex Seal lately, and I'm curious if it really works as advertised. I mean, it seems too good to be true that you can just spray it on a leak and it's instantly sealed. Can you tell me more about how it works and if there are any real-life examples of people using it successfully? I'm also interested in knowing if there are any potential drawbacks or limitations to using Flex Seal.