Thing is not hids are equal. If what your using is just a quality hid kit in a halogen projector it's going to be bright but not quality lighting. My previous cars were a 07 Camry I started with the crappy hid kit in the halogen projector and then I upgraded to a full hid retro using Toyota Solara true hid projectors and denso ballast/bulbs. Difference was night and day but the Solara hids are considered crappy oem hids. My next car was a Highlander that I had Lexus RX350 projectors put in which are arguably among the top two hid projectors available with hella ballast and bulbs this was a huge upgrade. My last car was a Acura TL and this car had the best hids I've ever experienced the cutoff lines were crisp the output was crazy wide but they were aimed perfect as to not blind anyone. So you can say I'm a lighting snob as I've wasted thousands on retrofits over the years. I've never liked hids in the fogs because years and years back as a kid I melted some fogs pretty bad as there not made to handle that kind of heat, but mostly they just blind everyone as there typically halogen enclosures not even halogen projectors. I normally leave them off with hids because i love seeing the crisp cutoff line with the different colors but There non existent with led bulbs.
As someone that had an HID wholesale partner for years,installed hundreds of kits, owned dozens, and also worked at a shop that did installs for HIDs both "cheap" and "quality" kits, I can tell you that aftermarket HIDs are largely the same. They put different stickers on the ballasts, change the wiring, add diodes and resistors somewhere in the wiring, etc.
Quality kits often have the load leveling stuff added as mentioned above, but definitely not always. They put the same cheap kits in a fancy box (which consumer behavior studies show has an enormous impact on perceived quality). The often also reverse the polarity of the plug because Japanese cars are reversed (but they do it to order) and there is quality control in place (meaning they test before they ship). The digital ballasts (95% anyway) are all the same. The analog ballasts were all 100% the same inside, I might add that they are far more reliable as well).
With "quality" HIDs they also send you the proper color temp more often.
In short, the cheap kits differ in the following ways:
1) packaging
2) ballast stickers
3) wiring changes (primarily anti flicker and error cancelors SOMETIMES included)
4) they're tested before they arrive
5) you don't get the color temp you order 1/4 times. They ship +/- one upward or downward kelvin rating and most people are none the wiser.
6) price
7) warranty (but for most companies, good luck claiming).
I've had kits taken apart by dozens of "manufacturers".
I've placed high and low quality hid kits in the same car before and have found that the color temperature is a huge factor in how they perform. An arc of light is an arc of light. The reflectors or projectors decide how the light is projected. If there's variance other than color temperature it's because the bulb is not seated perfectly straight in the housing.
Also, a projector is (for the most part) able to project light the same regardless of bulb type. That's what they're designed for. There are good and bad projectors, however. But a projector "designed for halogens" will be perfectly fine for HIDs. In fact, most car manufacturers use the same projectors for halogen and HID applications across models and even within the same model.
LEDs vary greatly, which is starkly different.
on your take on putting HID kits into Halogen designed housings.
