Collecting Guitars, Banjos, and Violins can be an expensive hobby and if not protected in some way they can be destroyed, damaged or stolen at any time. Many people keep their expensive instrument on a stand for display. It is a good way to show them off but they are not for storing an instrument and protecting it from damages or theft. Keeping it in a case will protect it from getting damaged, but it will be easy to steal and destroyed in case of a fire.
So what should you store them in? There are two options that offer the best protection:
The gun safe will work fine to protect any expensive instruments but it is not the ideal way. The way a fire rated gun safe works is that the fire retardant material sandwiched between the walls, pumps moisture into the safe while the fire is burning at about 1,000 degrees on the outside. In a home fire, the temperature of 1,000 degrees lasts for about 15-20 minutes. It then drops down to 400 to 500 degrees since it is running out of fuel. The temperature inside of the 1 hour fire rated gun safe would be between 120-180 degrees.
The problem, however, is that older guitars and banjos were assembled using hide glue which lets loose at between 120 and 150 degrees. It will be moving into a molten state by 165 degrees which is another reason you never want to leave an expensive instrument in a hot car. The moisture being released will make the un-gluing effect worse. Hot steam is one of the primary ways these instruments are intentionally disassembled by luthiers. So in a MAJOR fire a gun safe will not necessarily protect your guitars or banjos but if it is one of those one-room smoldering fires that the fire department puts out in 30 minutes or less then they should be fine.
The Mesa MBF7236E Gun Safeis 33" wide and will hold 6 or more guitars or banjos with cases and a top shelf to store anything else. A gun safe with at least a one-hour fire rating will give you the fire protection you need and the Mesa MBF7236E has a California Department of Justice Burglar Rating which will protect the instruments from theft. A data/media safe is the ideal way to protect a expensive guitar or banjo collection however it is an expensive solution. If you have a collection that is worth hundreds of thousands of dollars then it is worth it to go with a data/media safe. The inside temperature inside stays well below 125 degrees. Data/media safes are used primarily for tape backups, CD's, DVD's and hard drives for computer backup but they can also be used for expensive instruments like guitars, banjos and violins. The inside of the safe does not have a steam cloud during a fire and you can put "desiccant" bags inside to keep the relative humidity below 65%.
What you need to think about is what is more important: saving money or saving your expensive instruments?