http://www.fordgtforum.com/forums/showthread.php/33390-First-Modification
I've been running it on my car for 500 miles. Works well.
It's not suitable for high speed because it will affect the aerodynamics. But given the choice between rocketing the stones down the side of the door at 80 mph or trapping them in the front, it was a no brainer to trap them. The reality is, you're going to be pelting the area inside the nose no matter what, but for regular driving I'd prefer it not flying down the side of the car.
Let me know if you want a set. We just got some more in.