<This wont really apply if you need something with quick access for home defense, but it's something to think about if you use any of the locks mentioned in the posts above strictly to keep your kids out.>
Im just getting into pistols, so Ive been looking at this closely as well. Im sure some of you have seen it, but there was an article in Forbes, and there are some videos by DEF CON (hackers), that demonstrates that a 3-year-old can get into some of these safes (tragically, after a child was killed).
From a home defense standpoint, theres that decision of how accessible you need a firearm to be and abide by the laws of your state. But if you have kids/teens, or worry your kid could be peer-pressured into showing mommy/daddys guns, then I think you have to really consider a strong second line of defense.
Yes, virtually any safe or lock can be broken depending upon the determination, but if your concern for finding a lock/safe and quick access for home defense isnt necessarily a priority, you want to make it as discouraging as possible to avoid an accident. Taking out the mystery and educating your kids is the best tool of all.
Ive included the Forbes article link and the authors blog post, and the YouTube DEFCON videos below. Ill also counter the argument that these safes need to be mounted to avoid being tipped/banged, as the same shock can be provided to the mounted case with a hammer.
As for the Simplex locks, there was also an article on how easy they can be defeated. I thought I came across a pistol safe once that had the old fashioned, dependable turn the dial combination lock on it, but cant find it anymore. And I don't mean the thousand pound/dollar safes. I'm just trying to find something simple and small like everyone else.
I would like to hear if anyone has used the Omega system and what their thoughts are, as it looks like a great second-line
of defense against the kids. Cable locks are just too easy to cut by a determined teen. www.omegagunlock.comhttp://www.forbes.com/sites/marcwebertobias/2012/07/27/unsafe-gun-safes-can-be-opened-by-a-three-year-old/http://www.thesidebar.org/insecurity/?p=793
NSFW unfortunately quite a bit of foul language to make his point, but you can see the failures here. DEFCON 19 http://youtu.be/vIJFQO4DIxw
More from the recent DEFCON 20, meat and potatoes starts around 19 minutes; little kid breaking in around 49:55. Yes, the kid was prepped a little, but any curious kid or determine teen wont have any issue going this
route if they really want to get in. http://youtu.be/48HUctXZUNw
Defeat a Simplex lock http://www.forbes.com/sites/andygreenberg/2011/08/05/defcon-lockpickers-open-card-and-code-government-locks-in-seconds/2/
Someone else posted a great quote elsewhere: "Its a balance of convenience and security. The more security you want, the less convenience you will have. The more convenience you want, the less secure it will be. Choose wisely. "
Hope this is helpful to think about. No perfect answer that Ive found.