Just thought I should post an update.
Got a Tour X and went out for 3 hours yesterday on my standard GS1200. I'm 5' 10 on standard seat height, and the buffeting comes in at 50mph and sounds like a low frequency drumming and doesn't change much with higher speeds. It lets above average air through with vents closed and the visor mists up below 50mph at 12 C ambient temperature.
I will use it for Summer mostly as the peak is good for sunshading the eyes, and it is good up to 50mph with the visor up or half down, which keep the flys out. Sunglasses fit easily. Comfy fit and a nice strap clasp arrangement and probably it's best feature is the Offroad image on the GS.
For practicality, I like my Shoei Mutitec best. Versatile, Noise levels much better than the Tour X with the flip front and superb Shoei anti-mist system.
My Raid 2 is quieter again and good value. Just no flip front and used mostly in Winter. Beats the XR1000 because the fit and function are identical but the Vent controls are superior.
I am probably a Shoei biased head. I use a L Shoei, but an XL Arai. When measured, the Arai dealer said I was between L and XL, and an Arai L was a no go.