Why?
the risks seem too great wrt the continued existence of your bitcoin (no mention of mirrors), you don't have actual control of them because you've given them to a third party, there's no anonymity, and the costs are absurd. there's only a few entities i'd trust to keep data around forever, and random startup is not one of them. it would be easier, cheaper, and probably safer to put them in an encrypted and split wallet inconspicuously mirrored on multiple continents, or even an encrypted and split paper wallet duplicated in safe deposit boxes. the key to unlock the wallet can be safeguarded in a similar manner.
The problem is, that if mainstream adoption depended upon people using paper wallets, bitcoin would never work. People by-and-large aren't that technically savvy. One of the advantages of bitcoin is that such options exist, however, more traditional instruments can be created as well.
I would doubt that any insurer would insure a paper wallet unless they created it themselves, which Elliptic Vault seems to be doing. Otherwise the wallet might be compromised. At any rate, most people don't have the wherewithal to create a paper wallet. I could never count on my mother being able to do it. Everything technically interesting about bitcoin needs to be hidden beneath layers of abstraction for widespread adoption to be realized. I expect that over time, competition will drive the premium that Elliptic Vault charges down.