IIRC brushless are just more efficient in general. Since the power to the coils is entirely controlled by a microcontroller you can modulate how far "ahead" the magnetic field is of the motor, resulting in roughly the same performance at all speeds.

This as opposed to a brushed motor where the brush geometry in relation to the rotor sets the magnetic field a fixed distance ahead of the rotation. Resulting in the magnetic field being too far ahead at slow speeds and not ahead far enough at high speed.

In any case practical experience has shown me that a brushless motor is way more impressive than a brushed motor of a similar size and weight.