Steel rotors on 370z?

Originally Posted by DrBacon

No, bigger brakes does not exactly equate to better stopping distances. Pretty common misconception.

Your tires and even suspension is where that comes from. Having extra pistons on a caliper distributes the force on the pad and rotor which reduces heating for heavy brake use (many hard braking in a short time or lots of weight from a heavy car or towing something). As long as the brakes have the ability to overcome the traction of the tires then there is effectively no difference in a single emergency stop situation.