I purchased one of these this week thinking it would be ok on long rides with a visor for bugs, debris etc and at slower speeds lift it up and it would be like my RJ's Sturgis.
It fits well and is great on the freeway or really anwhere above 80KLMhr but lift the visor above 20klmhr and it whistles enough to test your sanity.
I rang the manufacturer to ask if this was normal and was told their open face visor helmets (and most others with retractable visors) are only designed to be worn with the visor down at all times and only lift them when you are stopped at the lights etc.
Might have been nice for the sales people to inform me of that before I purchased it. I have now modifyed it with a bit of rubber door sealing tape on the outside of the helmet when the visor sits when it is up to stop the wind whistling, it has worked well so far.
It will still be ok on longer country/freeway rides and it was good on the way home yesterday with 50klmhr headwinds before the storm came through, but if you are thinking of one for around town with the visor up, try and test one first.