Recently fitted a DB screen to my boxeye. Im about 5'10-11'ish and heres what Ive found so far compared to the standard screen:
- below 60, no difference whatsoever
- around 70ish theres a bit more wind noise/buffeting than usual if youre riding into the wind.
- above 80-85'ish and riding into the wind, unbearable wind noise and my helmet is being pushed back so far my nose is being squashed against my visor
So for legal motorway speeds, its fine. But for real motorway speeds, I find myself trying to tuck underneath the wind to make it bearable, but thats not great on your back for long trips either. I'd probably switch back to the normal screen, or look at getting a bigger/flip up deflector... but I like the look of the DB too much