No insurance. No way to prove what you put in the box. Fire or robbery wipe out everything you have. And though you never hear much about such things, fire and theft of safety deposit boxes were -- until this year --as common as bank closings. If you are frightened about the financial system, put your money in FDIC-insured bank accounts (up to $100,000 per named account holder). If you're scared to death, horde gold and water.
If you've got big ones, like me and The Famous Author, buy UYG on the New York Stock Exchange. It's an exchange-traded mutual fund of large, medium, and small banks and other financial stocks.