An option on the caravelle (not sure about other versions:
Laminated glass package with improved outside noise insulation. Z2A.
Basically, the windscreen and front windows are double layered, laminated glass. It does delete the std fit heated windscreen though, which is a bummer. The parking heater makes up for that though!!
Not sure how much difference it makes but driving at 65mph it's a very quiet place to be!
In terms of the wind deflectors, the side windows are very slightly thicker which means it takes a bit longer for the rubbers to form to the shape with the wind deflectors fitted.