You misquoted them. They didn't say the "best" they said the "farthest" for the Mazda. There is only so much light that can be produced by the lamp. Where that light goes is determined by the reflectors. For the Mazda to illuminate so far in the distance the reflectors must create a narrow dispersion pattern. This is not necessarily ideal as explained above in the article in the section on pedestrian injuries.

A well designed HID lamp will produce more light then a well designed halogen lamp. That extra light is channeled to the sides so as not to blind oncoming drivers. The wide dispersion pattern, combined with the higher color temperature, is what makes HIDs more effective (at least for the driver of the car that has them).

Here is the article.

http://www.consumerreports.org/main/detailv2.jsp?CONTENT<>cnt_id=302617&FOLDER<>folder_id=113261

-Dylan