Well, my bike has a smaller than stock screen, so there is more air all over, I am not sure about more turbulence at motorway speeds but a lot more bugs hit my helmet than with the standard helmet.
My problem with the Schuberth that I tried was that it shaked a lot more than my motocross helmet, which is a Shoei. The motocross helmet hasn't got that vibration, but is obviously a lot worse at catching air, not to mention there is no shield so there is a big hole catching air right there. I understand that a beak is never going to be ideal, but my question was about if there is any experience with one that is not so bad.
I love a modular helmet, because I ride with it open on slow speeds and love the feeling of opening it up right before arriving somewhere on a hot day. I would get an open face but the idea of getting a stone right in my face on the motorway doesn't appeal. But the beak appeals for touring...