The reason why I ask is because I like to do testing for myself. If the cutoff is a tight as the one picture I found from the DJ in Asia then it would be worth testing the amount of light is actually scattered. There are quite a few halogen reflectors that are perfect for HID's. One that comes to mind is the Jeep JK, scatter was only a third increase from a regular bulb. Not enough to even notice, unlike some where there is 2-3 times the scatter. If it is like the second one I found, it isn't worth my time or effort. It had absolutely atrocious output. So between the two I need a few more examples to justify the money.
But I plan on doing a D2S retrofit and since I already have the black headlights, I don't see the need to buy a second set.