but gun safes and locks aren’t really expensive enough to justify these kinds of purchases

This is the only thing I disagree with you on. A good gun safe and lock is incredibly expensive. Anything that's actually burglary rated is going to start at about $5k and go up from there. Good locks, like an S&G mechanical combination lock, can be had for a couple hundred bucks. (And by 'good', I mean the ones that the DoD uses for high-security; it would take an autodialer about a day, on average, to open one.) 'Good enough' safes are not too bad though, since they're mostly acting as a deterrent. E.g., little Timmy probably isn't going to spend a couple hours trying every possible combination until he finds the right one, and he's probably not going to take a pry bar to it.

Deviant Olam has a few videos up on gun safes, and also has a video of him showing what it takes to break into a DoD-approved safe (...that he was getting paid to break into). IIRC the general rule of thumb is that a gun safe should be 15-25% of the replacement value of your guns. If you only have one or two, whatever meets your state's requirement--if your state has a mandate about locking guns up--is fine. If you've got $10,000 in firearms--which is scarily easy to do--then you probably want to spend about $2000 or so on a residential security container. If you have a single legal machine gun, you're probably going to want to invest in a safe that's upwards of $10k.

I sincerely hope that they can find a way to make these work and be as reliable as a Glock. Not necessarily because they can't be spoofed, trafficked, etc., but because it would significantly cut down on accidents, and it would also make it much less likely that your own gun could be used against you.