I have several firearms that still sport open sights, be it shotgun, handgun or rifle all have fiber optic fire type sights installed. They just give a better sight picture for my old eyes, that being said I still can sight better with and prefer a scope especially when the light is faded during dusk or dawn. When I have to make a shot I want to have the best sight picture I possibly can have.
The Deer I took this year was a perfect example, walking through some pretty heavy cover at a distance of a little over 100 yds I would have not taken the shot with open sights as I could not be positive of making a clean hit. With a scope I was able to see small clear openings and when she hit one I touched her off and that was all she wrote.
Al