Well, we usually see them here on 1988 Hondas...thankfully, they were banned last year. Now they are being tuned down for OEM cars, for wider beams, but lower brightness.
You can seriously blind on coming traffic with HIDs. Especially helmet-mounted.
Since most accident are hits from the side and rear, HIDs have no safety value over LEDs.
In fact I can argue that they are more dangerous for night trail riding, they will flash on-coming trail riders and make their eyes useless in the dark.

A five white LED light, mounted low, will illuminate far enough to avoid hazards and last a long time on a charge. Much lighter too.