To answer your original question, yes, they work. I got one from Windblox. It keeps my hair from flaying my passenger (& the guy in the car next to us, probably). And it's quieter, too. Whichever one you get, it will make a difference. 92 degrees out today. Came home at lunchtime. Hubby got his bike out, I got my XF out. Lots of topless drivers. Supposed to rain this week, but this is the first sunshine in a long time.