I know this is area has been discussed several of times, it should be discussed again. We had it set up couple of ways, and tested couple of times, and in certain ways it is set up, it is almost 99.99% to break.
Having the vending vertically, yes you can twist the vendi out (but even at this, humans can burst at the vendi to counteract the twist between the vents). But if the vendi is flat faced down, it is almost impossible to get out. Even still if they get it out, by then, another vendi is placed that way behind it.
It can be broken, but, almost nearly 99%+ to break.