UKPULSE - Have you tried these yet, my concern would be that they rely upon reflection from a flash. On the road in daylight at the distance and angle the Gatso's are, there may not be enough flash to fully block out the Black, easily being recoverable with something like Photoshop,
I'm not saying try speeding past a camera :iraqi-info-minister: but set them at differing angles and distances and use a digital camera on them and let us know :)