Maybe it's good for you to know that retrofitting an HID kit into a lens or projector that was designed for Halogen bulbs will not yield the result that a purposeful OEM HID gives, because light properties are inherently different for the two.
Seeing this ebay offer the first impression I get is they are selling HID colors, most people are apparently very fond of the nice color effects of HID. Very few are really concerned about light quality and illumination. Many of these companies are just capitalizing on the fact that people think the HID looks "cool". So the low price isn't really surprising.
When I think about a good retrofit HID kit, I know it will never live up to OEM HID standards, but some companies actually put some work into their kits and it shows in the price. Like booya said, you get what you pay for. My 2 cts
