I posted that to lift your spirits. Now you can stockpile for at least 4 years. (The NAS puts the recovery time at four to 10 years.) As you know we've discussed the possibility of "smoke 'em out". Here is a short video on fire rated vault doors.
http://www.sportsmansteelsafes.com/vault_door_videos/sportsman_vault_door_video.htm The segment 4:35 - 4:45 informs us "if the wife hears a noise she can get inside and the perps can shoot an uzi at it all day long and not get access." At an $1800.00 tag it's a small price, indeed, to pay for peace of mind. A vault with a hidden air pipe to the exterior of the home would allow for extended stays in the vault. For further peace of mind a remote controlled booby-trap on the exterior of the vault should the hoards get access to your basement. Anything from tear gas to a home made pipe bomb would suffice. Also, a surveillance camera on the exterior would be a wise investment with a monitor in the vault allowing one to see if the "coast is clear". It's like restoring old cars. "Do it once. Do it right."