1. Brakes overheat, some systems earlier, some systems later.
2. Brakes will fade when overheated, some systems earlier, some systems later.
3. Brake fade reduces brake performance significantly
Better brakes can make a difference if you manage to overheat your brakes, wich does happen on the track when you actualy go fast.
However there is little difference for normal street driving if you don't live in germany...