Which brake fluid? One answer would be whichever you like. Seems like the all have their + and -.

DOT3 has great tolerance for water and is readily available and cost effective.

DOT4 has higher boiling point when it is dry but not so good wet.

DOT5 silicone does not attack paint if spilled and does not absorb water. The water just collects in the low spots. Heaven help if you do need to repaint where it has spilled however.

I drive mine "hot" time to time and run DOT4. I also change it pretty often to get the water out. I have also touched up the inner fender where the MC leaked and messed up the paint. No issues boiling the fluid.

They all work 99.9+% of the time.