I'll keep this one short.
While I agree that insurance is a great decision but on the other hand imho it is one that should be kept private and confidential to avoid any and all inquiring minds or thieves from knowing about your property and it's vulnerability.
Safes lined with asbestos do inherently store moisture, and sealing a container with moisture will give the contents inside little chance to escape any damaging effects that may result from this.
Not every place or situation is humidity free, even in Houston. Safes are great, and moisture control is another concern, or shall I say, it should be.
Just my 2 cents.