I was raised in Atascadero and I have lived here for most of my life. I think it is a peaceful and generally safe place to live. There is no major crime, as far as I can tell. Once my family's car was left running in the movie theater parking lot and it wasn't stolen. The town is clean and fairly safe to walk around. The air is fresh. Also, there are several high-quality restaurants.
However, the school system has something to be desired. The administration is difficult to deal with and funding is a major issue for many school organizations.