Not sure what kind of safetybox you got in your bank but over here they are just plain steel containers vary in size depending on what you pay. I got a couple of them though the service becomes less and less common over here. I don't see how storing drives in there would be a risk, just a hassle to keep them up to date.

Personally I just dropped a Synology at my parents place. They have a 1GB up/down line for watching her youtube video's and every week of my critical data they receive a copy. Relatively low cost, low power and easy to use.