Bolt hold open is a good idea either way you look at it. Here's why:
If God forbid you should actually have to use your rifle to defend yourself (AK), and you have fired the last round in the magazine, but do not know it, and sight in on a target with limited time to engage, and your rifle goes click, THAT SUCKS.
However, same scenario, and you recognize the difference in the sound / feel of your rifle when the bolt gets held open instead of cycling, you swap mags, and then engage target, rifle goes bang instead of click.
Simple.
The bolt hold open on an AK will not work the same as on an AR, but it doesn't need to, it just needs to inform you the mag is empty, before the rifle goes click instead of bang.
The difference between the mag swap and the click can be huge, when it comes to a defense scenario.
I wouls like to place an order on the bolt hold open followers, if I can find them again.