Well, Givi Airflow works by using special "compression box" between two screens. So, it doesn't even need to be as high as you may want it to be. Anyway, I'm taller then you and if I wanted, I could slide the screen upwards that much, that I could look only through the screen. Right now, the position is: lower screen on top holes, higher screen with its top edge leveled with my mouth (more or less). It still has planty of sliding to go up. As for a conclusion, wind noise is zero now, I don't need earplugs anymore. Buffeting is gone 90% and I found out those remaining 10% are not from the screen anymore but they are coming from the tank area, known for producing some buffeting (when I cover that area with my hand, all of the remaining buffeting is gone). I found on the other forum that blokes make windflaps for that area and they claim all buffeting is gone. So I ordered some material to play with and make those windflaps (it hasn't arrived yet).
Beside that, I'm going to try to tilt the screen a bit to the rider by adding some more spacers on lower bolts (Givi Airflow already has its own spacers). But that's just for play and curiosity. I doubt I can make it even better, as this product is excellent. When I was to order Puig, people were telling me to get Givi Airflow as that's the only one good for my hight. I wanted to save few quids and got Puig. Puig is high enough but buffeting is horrible. So, I got Givi Airflow and I'm hapy now (and Puig is laying on the shelf now).
I couldn't recomment it more, it does what it says and I can say that it eliminates all of the buffeting coming from the screen area. The rest of buffeting is from mirrors and tank area. I have swapped the mirrors to Aprilia Tuono ones when I got the bike, so I only have tank area now to work on.