Nosmo, The turbulence in my face from the Rifle is OK - I could and do ride with my face shield open at least partially down to 30 F in town at up to 55 MPH. The problem is the vortex air that wraps around and hits me at the back of the neck, which is pure misery on long journeys below 40F. I have to pad up my neck with balaclava and scarf so much that I reduce my head movement.
You may be right about the trimming, but I'm loath to try it without a fallback. I don't dare make it worse.
F-106, I can comfortably see over my current shield. In fact I think it's perfect, because if I slouch or tuck down I'm looking through it. If I had a taller shield I'd be forever looking through it, which I wouldn't like.
If the technical description of the Madstat system is correct, the beneficial behavior is created by having a significant airflow directed up and parallel to the back side of the shield, which balances the air pressure behind the shield, thereby preventing - or at least reducing - the in-rush of air behind the rider. With some aviation experience under my belt that makes total sense to me.
What I may try, before I blow significant cash, is to create something of a ram scoop to direct more air through the duct at the base of the rifle. If that shows promise I will splurge for a Madstat and report findings.
Thanks for your opinions, lads.