I've read a number of accounts online, and I know several 'smiths who've told me horror stories.
Also, after hearing these stories, I experimented with my K9. All I can say, is that Kahr doesn't want the sight to fall off the gun. Those suckers are TIGHT.
My sight tool started to BEND, and the sights still didn't move. I've been at this for a good number of years, and I've never seen any kind of dovetail sights like this. I suspect Kahr may use a heat/cold press fit, or other "shrink to fit" method.
To be fair, one smith I know says he's had no trouble on the several he's fitted.
I can say that if you give them a good rap, and they don't move, DON'T start beating on them. because the sight will upset and jam even tighter, plus you will scar either the sights or the slide.