Screens are like the bikes themselves, you need about four different ones in the garage depending on what you are doing that day.
My FZ1s came with a huge screen, i guess a touring screen, i chopped off about 6 inches and later tinkered with it to make a Vario type hinged top.
Now on the Italy trip it pissed down most of the way there so i was able to adjust it on the move and also check how the other three were coping with the sometimes torrential downpours.
I remanied dry except for the feet, even though i had carrier bags on my feet, it may of bee sweat,haha sweaty feet sydrome.
The screen in the upright position kept the whole of my body dry,deflected the rain up over the top,the others especially the gixxer 750 ,small screen was very wet top half.
When the conditions dried up the taller screen meant that with the increase in our speed the wind now being lifted to the helmet area was buffeted and noisey so i lowered the screen and the noise just dissapeared
But i shall soon be getting a smaller double bubble for English riding and keep a vario for touring,,it is a must, in strong head winds i lifted the screen and rode slightly in a ducked down position to get below the wind , that works to but dont get back ache as thats not good.