Biometric safes are great, as long as you don't think of them as "quick-access" safes. That was the mistake I originally made, but periodic instances of failing to open on the first try in conjunction with the necessary scan time made me re-think things a little.
Now I keep one gun on top of the safe, rather than inside, for quick access. It's up high. I have 3 little ones under the age of 8. If they were motivated to do so, I'm certain they could figure out a way to climb up and get it. However, they know they can handle my guns any time they wish (unloaded of course); all they have to do is ask, and be under my supervision.