Medical evac is EXTREMELY expensive, say at least $50,000.00. Stuff happens, regardless of how old or young you are. And if nothing else, everyone should have medical evac insurance, I think, as if you need it, you need it! And try to get a policy that provides PRIMARY insurance. What that means is that the insurance will pay UP FRONT, and you don't have to pay up front and wait (and hope!) for payment back from the insurance company. I don't know about you, but I would be hard pressed to come up with $50,000 overnight.

Here is a link to a FAQ that I did with general information regarding trip insurance.