Presumably I could chain it to something else large and bulky -- the bedframe, a nighstand, or a big bolt through the floor. We have an alarm, so as long as a thief was slowed down significantly, the time required to figure out what it's attached to and detach it should be deterrent enough. As long as it will withstand a crowbar attack it should be good enough.
It would also be pretty bulky. With a couple long guns and some ammo in there it should top 100lbs and be 4' long. You're not going to slip it into a pillowcase. A thief would have to be expecting it and be prepared to get it out of the house and into a waiting automobile. That would probably indicate an inside job, and any service people who had been in the house would be on the short list of suspects.
Around here burglaries are typically somebody going in and out a jimmied window with jewelry, cash, and smaller items that can be concealed in a jacket or gym bag.
Our house has 100% visibility from the street, and we know our neighbors very well. Anybody loading something into a car in front of our house is going to be noticed.
That said, the fact that I'm "defending" the idea indicates I'm not as comfortable relying on this type of security as I am relying on my bolted-down 1,000lb safe.
But as usual, avalability must be balanced with security.
