You don't need them. Regular, new, quality lights or even the 9005/9006 mod will work better than old, worn, faded lights. Possibly invest in HIR lights, that way you have brighter lights and you maintain proper beam pattern. If your lowered, re-aim your headlights so you get some light back.
But HID's will NOT be aim right, they WILL glare, no matter what you do.
And people will be fucking annoyed too.