Go to Rigid
and look up the distances they have for various combinations. They have some that reach out, some that have a wide beam, and others that are in combination. These are not vehicle headlights, per se; but the numbers will show you what the little buggers are capable of in the right body and in the right power.
Personally, I'd never use them for regular headlights; but there will be several of them on the front of my van for auxiliary lighting. I plan to put a couple of amber ones that reach out way far in the Aluminess as my fogs, a couple of wide beam whites on the outside of the Aluminess to see around corners and (hopefully) help with tracking in the dark--something I hope I never, ever do. I'll put some on a light bar over the windshield. I haven't decided yet what the combination of those will be. For some of those, I'm buying a clip-on amber cover to help with really, really bad fog or dust. Lastly, I'll put some less-powerful ones on the rear and sides.
I'm expecting the Rigid's to put almost no load on my starting batteries, even if the van's off for a short while, contrary to the halogen juice suckers.