I cant give my poly windshield away, completely useless even with the vents.... only thing i kinda regret buying for my machine, luckily it wasnt stupid expensive at the time. I dont mind the glass one I have now because its easier to clean and i can get it out of the way with three thumb screws... But it stays folded down on the hood until the mosquitoes go back to hell where they belong and the temps drop enough to not get hot while riding...
The soft sides really only go on for a couple months of the year so I can get the wife to ride in the winter and block a little of the wind. Although after she gets halfway through a cup drink she's normally warmed up enough from the inside to not give a fawk.
It'd be interesting to drive one of the HVAC rigs on the trail to see how much all that extra weight inhibits them... They gotta be more top heavy and not climb as well as a normal trail car due to the extra weight...