I swapped out the bulbs. They are D3S 35W and I put in 6000k temp. The stock are 4300k and yellowish. If I could I would move them up to 55w, but I do not know how to replace the ballasts. Be ready to rip up your wrists swapping them out its so tight in there! The proper way is removing the whole bumper but you can manipulate them in and out. I use DDM Tuning, but you can get them on Ebay also. They are cheap enough that you should get a spare in case one goes out, mine did.
The light is alot whiter, and to me brighter. The road paint, signs etc have a higher reflective rate with the 6000k. Here are two pics on a blacked out road.
