I like having a good windscreen in front of me. I like cutting most of the wind that buffets me during a long ride. I like having the bugs hit something other than my teeth. I like rain drops splashing on the plastic and then sliding up and over my head.
But I do not like their cost in terms of gasoline mileage or top-end speed. I do not like banging my forehead (excuse me - my helmet) on the windscreen when I mount my motorcycle. I dislike greatly not being able to look OVER my windscreen when things around me get dicey or visibility gets poor. I dislike reports of melted dashboards from leaving a bike in the sun at exactly the wrong time of day and pointed at the wrong angle relative to the sun.
As to 'aerodynamic', says who? Wind resistance is not just the angle at which you hit the wind. There is as much resistance caused by the vacuum behind your windscreen than from the wind hitting it in the front. The greater the 'apparent' surface area your windscreen has (the height times the width as seen from the front), the greater its resistance is, in one form or the other.
As to 'co-rider-friendly', what about 'rider-friendly' first? Have you ever driven at night and had difficulty seeing through your windscreen because your dash lights are all being reflected back at you from your new 'super-duper-swept-back' windscreen MIRROR? And should you get into an accident and find your head forced down by that windscreen that is levered over your head, what part of that new windscreen do you think your co-rider is going to hit first? (Notice how close the edge now is to her eyes?)
Like having that windscreen sweep around your grips? I guess you never did like the convenience of hanging your helmet using its D-ring and the peg that was designed to fit it?
Well, the larger screens look good. They are just right for some people. But do yourself a favor and take a ride behind one of them for a few hundred miles, day and night, before you decide to give up what you know works for one of these 'custom-made' monsters. The old one you already have just might be better than you think.