RE: ESC's. Brushed or Brushless WHY??
Basically, with a brushed motor, the wires that carry the electrical supply to the motor terminate at the brushes. The brushes control which windings of the armature receive current. The speed controller simply regulates the amount of current that gets to the armature. In a brushless, all of the windings are permanently connected to the wires. The speed controller regulates which windings get the electrical supply at any given time.