I'm 6' 2" (188 cm) with long back, 34" inseam. I've now tried followind screens on my V-Strom 800 DE, with standard height saddle.
Standard 800 DE screen, mounted on lovest or middle holes, is useful. Does not provide almost any wind protection at all, helmet visor is covered by flies just after 50 kms ride. However, for a long rider it allows quite free airflow to helmet, without notable turbulence. Useful screen for off road riding and for hot weather. I also tried PUIG screen extension and MRA Vario adjustable spoiler on the screen, but both cause quite bad turbulence on helmet.
Standard 800 RE touring screen. Provides much more wind protection for the upper body, since it's wider and taller than DE screen. When mounted in the
lowest holes does not cause so bad turbulence on helmet for the rider of my height. It is somewhat usable, but the downsize is that it blows most of the airflow direct on my neck, which feels a bit uncomfortable on highway speed. I also tried
Puig screen extension and
MRA Vario adjustable spoiler on the screen, but both cause quite bad turbulence on helmet.
Puig Touring screen. Wide and quite tall. Gives good wind protection on body, but causes quite bad turbulence on helmet. I also tried PUIG screen extension and MRA Vario adjustable spoiler on the screen. Puig extension does not help, but MRA Vario spoiler helps a bit against the turbulence. Puig Screen can also be bougth with adjustable Puig spoiler (just like the MRA spoiler I tried). I quess it could be quite good touring screen for shorter riders, up to 180 cm tall, offering good wind protection for upper body and not causing so bad turbulence on helmet (for shorter riders).
Tallest National Cycle VStream. VStreams have been great on my previous bikes, R1250GS and CRF1000L, but surpricingly it does not work on V-Strom 800. It's not so wide than Puig Touring or 800 RE screens, so it does not protect upper body so good. Without spoiler causes quite bad turbulence on helmet. Screen is good quality and very expensive here in Finland, and was therefore a huge dissappointment. I also tried PUIG screen extension and MRA Vario adjustable spoiler on the screen, but neither helped so much. Finally I placed about 5 mm spacers under the lower mounting points, also adjusted the screen to the lower angle, which also let a bit more air behind the screen. That helped and with the MRA Vario adjustable spoiler is the best touring screen solution for the rider of my height, from the four options I tried. It's far away from perfect, but is tolerable and the best of the options I tried.
I'll keep the standar DE screen for the off road and hot weather use, RE screen for the cold weather use on local rides and VStream with MRA spoiler for long tours. Its not perfet, but it's least bad. I would still like to try Givi Airflow, but wouldn't like to buy it, since I've allready spent about 500 EUR for screens and spoilers.
For the feel, finnish and quality, both OEM Suzuki screens and VStream are equally good, Puig screen is clearly cheaper made.
Puig Screen Extension
MRA Vario Spoiler
PUIG Touring Screen
Suzuki 800 RE Screen
National Cycle VStream