IMHO sun visors on a trad are a waste of time unless the hood is up (and who does that if the sun is shinning), The sun is always higher than the visor, a long peaked ball cap is more effective and cheaper.
Agreed.

They work well turned up to be above the screen. Also they are excellent at trapping rain in top down driving in the the rain& depositing said rain in onto the driver or passenger.
I agree 100%. I would not be without my sun visors.
If I was refitting them I would make the visors with a better coverage. The factory visors leave too much gap between them and the mirror an towards the windscreen pillar.