[Quicksilver]

4300K is WAY more acceptable then 6000k. If you look at the spectrum sensitivity of the cones in the eye it is pretty apparent that biasing the light towards blue is ignoring the fact that the green and red cones have a great deal of overlap. It only makes sense to use a light that is biased towards registering with more of the cones.
But 4300K H4 LEDs aren't available either...

BTW - Never said anything about yellow lights. I said yellowISH lights. And when using a completely subjective method of "Just asking people" they generally respond that the high powered lights, biased towards yellow, don't seem as obtrusively bright as the general "white" lights or "ricer bluish" lights. The more light I can throw downrange without bugging people the better.

-------------
Also - Just because the government studied something doesn't mean they didn't miss the point of it.
All of the research for headlights is based on how much light is being emitted. They have never looked at how it is being emitted.
- Example: Say you have two lights that emit the exact same quantity of light in exactly the same pattern. One light has an emitting area the size of a quarter and the other has an emitting area the size of a dinner plate.
Which one will be more glaring to oncoming traffic?

And that is the biggest problem with HIDs...