I never used them on any of my cars until I bought a Dodge Dakota pickup that had them installed already. It took about 3 days to figure out how good they are! Now I put them on all my cars. Yup....they look pretty old fashioned but they have a lot of advantages.
The main one for me is when I'm driving and the sun is to the side of the car, which happens for me 90% of the time, there is no glare at all in my eyes. It's like sunglasses for the side windows.
Plus run with the window open a crack for fresh air, even when it's raining (might even improve aerodynamics in that state...air doesn't rush in with the window open)
Plus reduces wind noise with the wind open a crack.
And if they make my car look ugly, it's less likely to get stolen!! Plus.