The Ford Mustang has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The BRZ doesn’t offer a front passenger side knee airbag.
The Mustang has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. Only the BRZ Limited offers a blind spot warning system.
To help make backing out of a parking space safer, the Mustang has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Only the BRZ Limited has a rear cross-path warning system.
Both the Mustang and the BRZ have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras and available rear parking sensors.
The Ford Mustang weighs 610 to 1117 pounds more than the Subaru BRZ. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts. Crosswinds also affect lighter cars more.

