Gomiata,
I am the Field Services Manager for a company that supplies most of the weapons/classified document vaults to the government. Any good vault and safe tech should be able to defeat a safe after having a little time to examine the locking/latching mechanism. A good thief is capable of doing the same. The problem I have with commercial gun safes is they are available for inspection in multiple places, with brochures describing how their mechanisms work.
When I built my personal safe, I did it in a way never done
before, with a locking mechanism of my own design. It would take a while for anyone to get in, even a skilled vault tech. I am completely confident that no burglar would be able to open this unit. Unfortunately, the way it is designed, any forced entry attempt disables the mechanism, and the only way in at that time is cutting it open, even for me.
Any commercial gun safe will provide the average gun owner with protection from the typical home break in. For examle, a druggie, or a couple deadbeats looking for some easily obtained loot. If you are looking for protection from any skilled burglar, the vault door on a poured concrete vault is a much better option.
As for fire protection, take that with a grain of salt. My safe is made of 5/8ths" Astroloy plate. For heat protection it has a layer of 5/8th" cement board against the steel, followed by a layer of 1 1/2" Kaowool fire blanket, then a second layer of 5/8ths" cement board. The final interior finish is a high temperature textured paint. I didn't want anything flammable next to the items inside, so no carpet. I don't know what the outcome would be in a fire, but I would not expect things to be undamaged.
If you have a high dollar collection, I would opt for a custom built safe, or better yet go with the reinforced concrete vault and a GSA certified vault door. A monitered home protection system, would alert police and allow them to respond quickly enough to stop the thieves before they could open the vault door.
