I keep mine on a broken raid 5 array (seagate flood drives - two failed within hours of each other) in a shoe box. It’s super secure.

RAID is cool but It's not much of a backup then if it's always plugged into a running computer. Half of risk comes from some process "intentionally" the erasing the data.

I use the super-sophisticated method of manually copying everything important to an external storage another every 5 weeks or so. That has never failed me.