I have a wall sconce in my room, which is attached to the wall with two expansion anchors (dowels). They look well-fixed, but, AFAIK, they are about 20 years old. Do you know, how long dowels last, and whether I should replace them because of their age?
I found the Wood kind of my Grandfather in my House. They are just fine. The plastic once should last even longer. Don't fix them if they don't need fixing!