Always best to check with the bank you use regarding what their policy or state law requires in the event of the death of the owner or co owner of the box, and procedures for access to the box by the co owner, co signers, executor or other family members after such a death. It can vary by state.
Also, if you go the home safe route, no matter how big and heavy it is, it is best to have it bolted to the floor as Jeff mentioned. I have seen first hand the damage done when thieves drag a large safe out of a home. Seems like the bigger it is the more valuable they think the stuff inside must be
