It is not a good idea because i already experience problem about 4 digit and the receiving the code when loging in.. honestly until now i can not log in there because of their security and i contact their support but never receive any email to them so i ignore because i have only few sat there..and use it before when i was xapo faucet collector..

For me it is good and safe wallet is bitcoin-qt or electrum for lite version that you can backup your wallet.dat and private key that you can install to other wallet once electrum will crash or hack.