New member here, just bought an e90 325i three days ago.
I used to do alot of work with lighting and did the first TSX retro on an E36 with comparo pictures to show how outdated the ZKW pattern was.
The E90 has a very blurred cutoff with a lack of "colorband", so when you see an e90 coming at you, it doesnt look as impressive as the Audi's or certain E46 xenon equipped cars. The E90 has splotches of yellow as a colorband.
You guys should probably avoid the 6000k and higher kelvin temperature crap, they're a fake solution to the true blue's and purples you see out of Audi's and Porsches.
You can adjust the focal point of the cutoff shield with washers or shield bending with your existing E90 headlight setup if you're brave enough to disassemble your projectors to produce this:
Here is the sharp cutoff from my E36 TSX retro:
Here is a picture of the shield that I am referring to that the cutoff comes from: (picture from a TL projector)