From my experience, and from some others I worked with who use guns for the most extreme circumstances, if you go with dot sights on your self defense handguns, you go totally dot sight on them.
Between irons and dots, there’s enough difference on how the gun has to be presented to acquire your sight picture, that switching back and forth will cause you to take extra time to get on target.
And since time is of the essence if you need to use a gun to defend yourself, you can’t afford to waste any chasing the dot down.
So, it’s one or the other. Don’t mix them for your self defense inventory.