Few points to bring up.
Headlights do have specific aiming requirements, and while they do not change per vehicle, the legal requirement for the placement of headlights is enforced. As i recall, headlights may not be more than 3' off the ground, and while its rarely ticketed, techinically, most lifted trucks break this law. That is why, even if you do have properly aimed headlights in your lifted truck, they are still illegal.
Anybody who claims that HIDs in reflector housings increases output is quite confused. HIDs do not produce the same sort of output as halogen bulbs, and as such, light scatter is far more evident on HID vehilces. In fact, installing HIDs in even halogen projector housings causes major scattering. The bulb is a very different design and should be treated as such. You also lose high-beam capability, which can be essential for night time driving in remote areas.
When installed in a proper HID housing, HIDs provide solid, consistant lighting and with a bi-xenon setup, unbeatable output for both high and low beams. All of this, while maintaining DOT standards.
Im not going to bag on anybody for installing HIDs in reflector housings, its their choice, and so be it. But just let it be known that the only gain from doing so is in your head.
Your choice, spend $100 on a crappy ebay setup, or spend $279 on a RetrofitSource kit.
If you want sources, i had a 6000k HID setup in both my stock reflectors, as well as in halogen projector housings, Neither held a candle to the stock output. The setup i have now through theretrofitsource puts even machs to shame.