I am also cursed by the XD + 950 wind screen problem. But I fixed most of it.
Better wind protection and buffeting:
XD Noisy: Jammed ear plugs into the top two vents.
XD Visor Buzzing: Helmet Skin
Also makes my silver XD more visible. But the Helmet Skin tends to flap in the wind. I stuck the single fuzzy side of Velcro on the inside of the skin to stiffen it up.
When it comes down to a 3 hour freeway only ride at high speed, I just take the XD visor off.