My former employer makes a camera-based lane departure warning system. Although I was not involved with its development, I do know that the amount of testing that they do on these systems is very extensive (hundreds of people involved in the test process).

I would be very interested in seeing a side-by side test of the LDW systems of major manufacturers. This might give us an idea if the problem is fundamental to the technology or is simply a deficiency in the engineering approach of one (or some) manufacturer(s).