Shoot some water based paint through it & see how it does. It could turn out to be really handy. I repaint lawn furniture, new trim & baseboard before installing, etc. & find such devises really useful. If you have no need for it, I'd give it to a friend before I pitched it.
I have one of those similar style and it worked perfectly well for me. I painted some vintage cabinets that I sandblasted first, nearly a hundred years old.
