I think it depends on how they approach the wings. Most street bikes don't go that fast and those small wings and pretty traditional body panels just aren't going to do much. In fact, I bet the wings are positioned to be as neutral as possible aerodynamically. Still, who knows what will happen to pass that truck at 90 mph on the highway? But think about it: We ride with stuff tied down to the rear seat, clothes flapping, moving all around in the air stream, or even with a passenger, so how precise can the airflow really be? I am sure these wings are designed so that don't actually work!
On the other hand, my BMW K1600 was the spookiest ride ever in the wind. I have gotten EST (excessive sphincter tightening) even just passing an SUV. It was a combination of the huge flat front of the bike/shield and the very twitchy balance of the bike. That was a really dangerous bike. With panners, BMW limited the speed to just a little over 100 mph. Made me wonder what the complicated 6-cylinder engine was even there for! The Busa is exactly the opposite - super stable. So I doubt the wings will matter (at normal speeds of course).