My experience with the Aeroflow is kind of like yours at the speeds you mentioned.
I'm 5'9 with a 32" inseam. Baldwin GT seat (taller than stock) and Wedges. I usually sit straight up (not slouching) and my butt is all the way back in the seat so I probably sit taller than most people that are my height.
At lower speeds (under 65mph) I see what you are talking about. Nice cone of silence. For me, the amount of slight breeze is enough to keep me cool. Nice to be out of the blast of wind. I too tend to have the shield at about halfway up. All the way up, I look through the screen.
At higher speeds (80mph and above) The stock windshield lifting system tends to push the windshield down a bit. At full up, I am now just peeking over the shield. At speeds such as this, I tend to have the windshield at 3/4 up. With the shield all the way down, I get a nice smooth blast of air on my chest.
The amazing thing about the Aeroflow shield, in my opinion, is the difference in turbulence between the stock shield and the Aeroflow. The stock shield has so much noise and turbulence that is almost unbearable. The Aeroflow has virtually no turbulence noise at speeds below 65mph. At 80 and above, I just get slight wisps of turbulence. It really is amazing.
I've ridden in 100 degree temps and the Aeroflow seems fine but then again, I havent tried the other aftermarket screens.
Aeroflow does make the screens in 3 sizes. The screen I sent to you for the demo package is a Large screen. Maybe one of the shorter shield would be to your liking?
EDIT TO ADD:
oh yeah.. Paige at Aeroflow designed some trick hand wings but I felt the bike didn't need them... I just realized from reading your findings that I might be a bit off the mark because of my bikes modifications.... I have Wedges installed on my bars which (among other things), brings the bars closer together. That difference, along with your bar risers and lower 08 mirrors could be the difference. I'll talk to Paige about this...
Jose Soriano