I drove from dusk until almost 2am w/ my headlight covers on (Headlight covers = very little to no light output from headlights) coming back from the National meet in Dallas. Thats about 5-6 hours of highway driving, through dark no streetlight sections, with the 510's installed, not a problem.
I even managed to piss off a few truckers b/c they were aimed kind of high at first!
