I would stay - but then again, I am not afraid of bats or most animals. We had bats in our home and had to get vaccinated. Once you are vaccinated for rabies, it's really not unsafe to live in a home where a bat may get in every now and then. I tend to view bats/mice/ants as a natural part of life, as long as their unwelcome visits are few and far between and I am otherwise happy with the cleanliness of my environment. If you are going to hate your life always worrying a bat may appear though, you should probably move.
Edit: Just read your update on the other thread. It is very possible the issue will be fixed permanently with the removal of the nets. Bats tend to return to the same place over and over, like we do. If they are blocked out, they will try to return for a few nights. Once they realize they can't come back, they move on to another site and won't revisit. This is why one colony of bats can literally move down a neighborhood over the course of a few years...they just go house to house. Still it may be reasonable to demand that the landlord permanently patch any unnecessary holes in your walls with drywall and plaster so you can be sure.
