Please do not take offense to my postings, as I said I'm only here to inform you. I understand that everyone else jumped on you but just ignore them if they aren't providing any helpful information. All I want is to help you see this properly because a lot of people put HID kits in their vehicles without understanding how they work and become extremely ignorant when told otherwise because people attack them. I personally don't think it's irresponsible if you aren't informed, if you are informed and still do it then it becomes irresponsible
Now that that's out of the way I will offer up some explanations for you.
As he said above, those Cadillac headlights are designed specifically for HIDs, the way HIDs output light is completely different then Halogen. Halogen is a filament that is heated and outputs light in a different pattern than HID capsules which create an electric arc to produce light. There are reflector based HID lights but those are old and they are designed differently to halogen based reflectors. They also use different HID capsules (D2R and I believe D1S) that have a built in shield, there are no kit style HID capsules in use in reflectors. Older Acura TLs used them as well.
A lot of people think that because they don't get flashed their lights are fine, I'm sure if I aimed my normal headlights up enough to blind people that maybe only one would flash me. I've seen plenty of people at night with high-beams on and I'm the only one to flash them. I usually don't flash even because the people are either behind me and I'm not going to slow down to flash them or they're driving by and it's only for a second. It's not a good way to measure your lights "blindingness". Park around 25 feet away from a wall on a flat slope and you will see how much of the light ends up higher than a normal car's roof even.
For sure the HIDs will be brighter than halogen even if you pick up 10,000k because they output a lot more light, but an HID capsule at 4300k will be brighter than a 10,000k HID capsule I can guarantee you. Not only than, a 4300k HID capsule in a projector will blow away anything HID in a reflector because the beam will be smoother, wider and more intense.
Just look at your Lamborghini versus Porsche picture. From pretty much the same height and same angle of the cars the Porsche's light is a blob of light, that means that from where you were standing the light will be bright, and I will take a guess that you were standing up right (meaning your camera was probably at roof height of a normal car). The Lamborghini has a much tighter circle of light because it is cutoff at that point. Trust me it is really uncomfortable to be driving in a car at night in front of a car with an HID kit, even worse if it's an SUV because the lights are already harsh being at a level that shines into your mirrors, HIDs being brighter make it even worse.
I can guarantee you 100% that any vehicle with HIDs stock (not sure about reflector based ones but the projector based ones yeah) is using 4100-4300k capsules. The reason the Lamborghini looks purple is because of the cutoff, think of it as a prism (the lens) as it works the same way. The cutoff is the only part of the beam that is colored. Again, park 25ft away from a wall and look at the wall, the line on top will be coloured but the rest of the light will be white. That's why BMWs look blue, it's the way the projectors are designed, not the color of the light. The light on the ground will always be white. Call any car dealership and ask them what color temperature their HID capsules are, they're always 4100-4300k. The companies that actually supply capsules (osram, philips) to the car producers do not produce anything above 6000k anyways.
Anyways, there is another way to get HIDs the proper way, it's called a retrofit. It involves taking the projectors from a car with HIDs and modifying your headlight with them, that way you can have HID projectors in a vehicle that never came with them. Check out
http://www.hidplanet.com, they hate kits over there (be careful) but they are extremely knowledgeable.
Nobody might be crashing because of your lights (though it is a possibility), but trust me, it would be greatly appreciated by everyone on the road if you do it with projectors.
Thanks for taking the time to read and sorry for the long post.
If anything is not clear I would be glad to clarify it, just let me know.
(BTW, a few of the other people who posted their HID kits on this site got eaten up because people rather insult and attack than educate)