I run "Silver Stars" in my passat, there pure white.
The reason that the HID are illegal to upgrade is because the reflector is built completely different.
A HID "PROJECTOR" housing has a hard edge cutoff at below 50% so your eye never sees the direct bulb intensity, unless your at thy level, or the car goes over a bump ant tilts up.
light passes below the bulb so not even reflected light is allowed up to eye level at any where near full intensity.
where a normal h2 h1 or h5 bulb has its full intensity out where its completely visible, in the center of a parabula, focusing all light, direct or reflected at a forward direction.
so sticking a HID bulb in the stock non projector headlight causes literally blinding to the drivers in front of you.
I hate the guys with the legal HID lights in the Caddy SUV's where they pull up behind me and light up my car like its daylight inside at a stoplight...lolol.