I'm really not going to go over the steps on how to install new HID bulbs in a B8.5 S4 as there is many Youtube videos out there to cover that. I will let you know that you will need to remove the Air intake box on the passenger side, so plan a head on that. I will warn you these are 4200k color so they are white with a hint of yellow. For those of you that want the pure white, well these aren't going to be your bulb. I like them because simply because this color works better for all weather situation. 5500K and higher bulbs have a hard time illuminating wet roads like what we experience in the Pacific Northwest, so the 4200k is the ideal color.
In summary way brighter, and I'm happy I got them. Sorry pictures won't do justice so you will just have to take my word for it.