Well, lemme chime in:
There is no 'best' aftermarket windscreen for the general population. Everyone's height and riding posture is different as is the individual bike set-up (seat, farkles - yes farkles, etc). Each of these factors will have bearing on how well the screen of your choice will affect wind flow, etc.
Here's my recent experience with the VStream...
I've been perfectly content with the stock screen on my '05, preferring to leave it in the down position - until I got my VStrom. It was then that I noted an unusual amount of wind noise (meaning; I never noticed the wind noise before, but it was there), especially around the left side of the helmet. It was becoming deafening, so I sprung for the $136
version of the VStream. Mind you, I rode a stock FJR with the VStream and the ride was very quiet and un-buffeted, so I had no doubt that this was the screen for me. Wrong.
I slapped the screen on and the effect was little different than the stocker with merely a slight rise in the way the air hit my helmet and did nothing for the noise. Just by happenstance, while doing the preliminary testing, I rested my hand on the Skyway cruise control bracket that had recently been installed (at about the same my VStrom arrived) and guess what? The left side helmet noise went away. (Note to self: Call attorney to begin lawsuit proceedings against skyway for making me go deaf! :lol: ) However, the major part of the wind noise remained regardless of shield position.
While cruising around Death Valley with a bunch of other like minded misfits this weekend, I had occasion to raise my visor while at speed (to remove a disruptive piece of coagulated snot from my left nostril) and all went silent. So, merely lifting my visor in combination with the screen raised 2 inches gave me a quiet pocket.
In this case, I proved that the combination of the screen, my bike set-up (mostly the custom seat and risers) and my Shoei RF1000 (along with that damned CC bracket!) makes for a bad selection of screen for me or so that’s how I feel right now. I’ll fool around some with RadNutz ™ to see how they affect the flow. Right now, I’m just not into spending a wad of cash trying out umpteen different screens, especially since I’m in the market for a new lid that will change the flow once again.
So, take what you learn here and flip a coin on what might work for you. The good news is that any screen that you buy and find that it doesn’t work, can be sold here for half the price you bought it at!
