Standard HDT lighting is restrained in that the headlights are typically mounted high and have to be limited to prevent blinding other drivers. This is usually limited to 100' for low beams to the left side.
Couple that with the erosion on the plastic lenses of the headlights and HDT lighting is poor.
There are numerous LED and HID replacement bulbs in the marketplace but most are not legal let alone effective.
David Dixon of Deep Space Lighting has done extensive research of the regulations and needs for better lighting and has covered the option and the kits he has developed to provide legal improved headlights for you HDT. Check his site for information of how to best improve your headlights.