I put a 20-inch Nilight light bar on mine back in the spring. No issues, though the switch I installed for the light has an LED illumination that runs all the time, since the light is hard wired to the battery and not running through the ignition key shutoff. I am sure it is a very, very low/slow draw, but I just keep the machine on a trickle charger when parked for extended periods in the garage.
As far as the light itself, works great and really lights up everything in front of you like high noon in July!