This thread is scaring me a little.
I used to drive a Mazda Protege before my E90, and speaking for every person out there who drives (or used to drive in my case) a low-riding car that doesn't have auto-dimming mirrors, please please be careful how high you adjust your headlights.
From the perspective of a E90 driver, I love my xenon headlights.
However, I remember how much I hated xenon/HID headlights when I was driving my Protege. I would be blinded almost every time a car with xenons would pull up behind me or approach me from the opposite direction on a 2-lane road. I think a lot of people don't realize how bad the problem can be because so many people drive SUV's and trucks that obviously ride high. However, I can assure you that anyone that drives a small compact car that rides low to the ground is covering their eyes and cursing under their breath many times when a car with xenons drives by. Don't even get me started with SUV's/trucks with xenons. So please be conscious of the other guy when your adjusting your headlights.
Ok, there's my good deed for the day. I'll get off my pulpit now.