Since one of the topics is upgraded headlights, I thought it wouldn't be a complete hijack of the thread to post my solution to another night driving problem - glare from headlights behind you.
I picked up a tinted sun visor at PepBoys, cut it down to size and super glued some magnets on it. It eliminates headlight glare completely. The image is a slight double image due to the distance between the tinted plexiglass and the mirror, but that's not an issue at all - can easily see what's behind you without being blinded.
An eyeglasses pouch was perfect for storing it in the glovebox.
Kevin