1) Lights aimed properly will minimize glare 2) Getting lights with spot/driving pattern are the only ones I would mount on the windshield hinges. Floods will guarantee that half the pattern is spilled onto the hood.
I have some KC lights (driving pattern I believe) mounted on my windshield hinges on a white jeep. Do I get some glare? Of course. But I also have the lights aimed outboard of the midline of the jeep. This is because I use them for their intended purpose - offroad lighting (and sometimes on dark backroads to see deer better at night). Aim the lights correctly and you will minimize glare. And honestly, you shouldn't be running lights like that on the road just whily nilly. They are too high and bright and will more than likely blind oncoming drivers regardless of how you have them aimed.
Also, if I'm running my windshield lights, 95% of the time, I've also got my brights on. They don't add much effective distance on the road with the brights because the beam is like a pencil, but they do add very bright light just outside of the spill of my head lights, where I need better illumination of the sides of the road/trail.
