I see those 5 services at best as scam, as BS at worst.
A better way is to travel to Geneva or Zurich, sell your BTC there via localbitoins and buy gold with the cash.
Then it's easy to store your gold there in a vault.
While I don't know those companies isn't having a gold certificate stored on the blockchain pretty secure, well as secure as and ownership of Gold in a vault ultimately? I mean if you have the claim on a well run vault in a 'safe; country thats quite safe, I mean its not an ETF or something that is ownership of nothing.
Sure holding is ideal but its not always practical plus tax is an issue in most countries.
What are the safe countries if you have stored gold anyway? I'm thinking Asia is the safest, maybe Hongkong or Singapore. I could see confiscation happening anywhere in Europe.