Just a couple of thoughts, FWIW. Trusting the security of what could be several thousand dollars worth of firearms to a $200 cabinet seems like a false economy to me. Don't get me wrong here, ANYTHING is better than nothing and a lag-bolted cabinet will at least slow them down and force them to make some noise.
Lots of folks seem to buy one of the cabinets instead of a real "safe" for reasons of convenience and portability as much as economy. Anyone who's ever tried to wrestle six or seven hundred pounds up/down a flight of stairs likely isn't hankering to repeat the experience. Renters and people in occupations that require mobility generally are daunted by the potential hassles of dragging all that mass around.
I was one of them until I got turned-on to a design that, IMHO, gives one the security of a real safe with almost the same ease of portability of a cabinet. An outfit called "Zanotti Armor" makes it, and it's a winner.
As their website is still "under construction", I'll give you the basics here.
Offered in sizes for from 16 to 52 guns. Weight ranges from 400 to 925 lbs respectively. All are designed in six interlocking pieces shipped in three or four boxes from the factory. The largest single packages weigh from 110 to 175 lbs, so delivery and installation can be accomplished without informing the whole neighborhood that you have a safe. The body is made from 1/8" and 3/16" steel; the door of 3/16"; the locking bolts of 3/4" hardened steel; and there is a triple-relocking system in case the combination lock is tampered with.
I used my tax refund to buy the 52-gun model. My brother and I carried the pieces down to the basement and assembled it in less than an hour. All of the panels are interlocked by 3/8" nickel-plated steel "L" pins that slip into sections of steel tubing welded to the panels inside. It's a very tight slip-fit, and the assembled unit looks like it's monolithic. All of the parts are hand-fitted at the factory, so alignment is perfect.
My cabinets are now relegated to ammunition storage and less-valuable guns. Our most-cherished items are in the safe. Without this modular design, there was just no practical way for me to have a real safe large enough to hold my collection unless I was willing to have it somewhere in plain sight in the main living area. Our home was built in 1912, and any single one-piece design even halfway up to the task size-wise just couldn't be maneuvered anywhere else, even with a platoon of help.
It wasn't cheap, but it was a bargain. The savings on my homeowner's insurance premium's firearms rider will pay for most of it in five or six years.
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