Initial thoughts are, wow these are bright. Factory halogens don't even compare and I can already tell it's gonna take some time to get used to the dramatic cutoff.
After some driving last night, I decided to aim my headlights a bit lower than stock. I just feel bad coming up over a hill or hitting some bumps and my HID's are most definitely blinding oncoming traffic.
Also, I've noticed that right around the cutoff point, the light has a purple color. I really notice it when white road signs light up purple. My bulbs are Morimoto 5500k.
As far as installation, it couldn't have been much easier. Phil from Fastheadlights.com was very helpful and recommended the Hylux ballast over the Morimoto. There is no wiring to the battery and no relay harness. Super easy.
It was a bit time consuming, and the hardest part was cutting open the factory lights, but I took my time and everything turned out great.
Driving down a dark country road with the brights on is just about the coolest thing ever haha.
IMO, the LED fog lights are a must-have when you have headlights this bright.
Hope this helps!