I'll ride with a screen. Without is fine if your just tooling around town...but up on the slab for a long days ride a screen then becomes indispensable.
The degree to which a good screen and lowers removes the onslaught of the 80 mile an hour slipstream is phenomenal.
Ride 800 miles in a day without one and you will feel the last two to three hundred miles in a big way....ride with one and those last two to three hundred miles can be as nice as the first five hundred. NOT getting your face and neck beat by that onrushing slipstream is a GODSEND at the end of the day.
Ride in subfreezing cold without one and then try it with one and note the difference in comfort.
If you wear prescription glasses or shades.....you can cruise at 80 miles an hour with no buffeting to same.
You still get enough breeze for that in the wind feel.