If you are the type to buy a plug and play kit to slap into your housings; you shouldn't. All you are doing is creating a horrible beam pattern and blinding oncoming drivers. There are proper ways to make your car have HIDs; buying a kit and slapping them into a halogen housing isn't one of them; but if you're going to be cheap, at least put your HID kit into a projector housing.
READ THIS FIRST
So you're driving around and you see them, those "blue lights" commonly found on higher end Japanese and European cars. Well, you want those lights on your 3G, you really dig that blue look, you think it is neat. Good for you. There are things you need to understand before you slap on a pair of bulbs on your ride and not only endanger yourself by not being able to see correctly, but other drivers, by you glaring the **** out of them.
First off a thing about the lights, they are called HID's and that blue/purple you see coming off of them on the cars has more to do with the color band in the projector assembly and not the temperature of the bulb. Every single OEM manufacturer with a headlight projector HID system uses some variation of the temp 4300k, not 6k, 8k, 12k, etc.
Why don't the automobile manufacturers use these higher temp lights like the 6k, 8k, etc? Because the higher the bulb temperature, the less the light output as the colors being displayed are getting farther from the color of daylight and your eyes can't see them.
So what does this mean? It means all these fools rolling around with anything higher than 4300k can't see as well as someone with plain ole halogen headlights. Huh? I am sure you've read all the posts and threads in here talking about people claiming they are seeing better and farther than Superman because they've slapped on some 'tite' 10k HID bulbs in their headlights. No, they aren't. What they are doing is introducing a flood effect of the light, and glaring more area, but the laws of science and physics have repeatedly told us now it is physically impossible to see farther than the light temperature of daylight.