Safety will always be based on ones personal experiences. You can feel safe in an unsafe area because you are naive, or because you know you can take care of yourself and those you love.
The big draw for the RGV is cost. I think that is what a person will find out if they venture there. From that a person can then decide if the savings is enough to overlook things, or should they pay more and move on to a place that those "things" aren't around.
For us we enjoy the Valley and the people in it. We do pay extra to be in an area that we perceive to be safe at all hours. We go out of our way not to go to areas that we perceive to be unsafe regardless how cheap they may be. Bottom line is it's an individual choice only you can make based on your life history.