[dayman]

I have a non biometric GunVault - it has a 3 digit combo, so no batteries to worry about changing, and it was relatively cheap on Amazon. It's worked well for me. For nightly storage I keep the combo set so all I have to do is turn the handle to get it open, but if for some reason I have to leave my gun at home for the day I can scramble it.
I can also bring it out to the car easily for times when I might have to leave my gun there.

While it would be possible to guess the combo, anyone with enough time to guess would also probably have time to cut the cable and just take the whole box, or take the drawer from the night stand, or smash/pry it open with a hammer/crowbar.
I think pretty much anything other than a full size bolt down safe is only going to prevent kids, idiot house guests, or very casual thieves from getting to the gun, and to that end you don't need anything too fancy.