Originally Posted by Belarus
If you don't track your car and haven't upgraded your brake system why would you want to use another brand if your car is under warranty
Considering BMW US covers regular brake system service including brake fluid flush as per their 2 year schedule if I'm not mistaken.
Because you will boil the stock fluid in 2 laps on the track and have to nurse the car for the rest of the session with faded brakes. It doesn't have much to do with upgrading your brake system. In fact, a stock brake system stresses your fluid more because it gets hotter.
A fluid flush with Motul 600 is not expensive when done yourself. And no, there are no warranty issues, just use any DOT 4 fluid you like.