The 4300k temperature was considered the ideal color temperature at one point which is why it's an OEM choice for many car manufacturers, best for all situations like rain. But MB will sell whatever the market demands.

The V notch got burned into the headlamp housing and Mercedes even had a special liquid to clean off the notch.

 

5000k works good for me. Honestly, it's barely noticeable difference in from that to the 4300k. (Using my boss's '02 GS as a reference.)

As for the V notch, I'll keep it in mind.