If HID lights have been around long enough for anything to be called ‘old school’ then that’s what you’d call the Nite Rider Flight.
The battery is smaller and lighter than the first incarnations, but it does fit to the cross bar in the traditional way. The beam is tight and powerful and there’s the option to switch to LED to save power – but in our experience the tiny bulbs are best for emergency use. And it’s a niggle, but the bar attachment sits quite high which makes it prone to vibration. You can attach it to your helmet, but the unit is heavy so make sure your lid fits well or you’ll give yourself neck-ache. Much as we’d love this power (if we could afford it) on the road, this wouldn’t be our HID of choice for the trail.