The BMW X3 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 GLA doesn’t offer a front passenger side knee airbag.
The X3 has a standard front seat center airbag, which deploys between the driver and front passenger, protecting them from injuries caused by striking each other in serious side impacts. The GLA doesn’t offer front seat center airbags.
Over 200 people are killed each year when backed over by motor vehicles. The X3 offers an optional Active Park Distance Control that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The GLA doesn’t offer automatic braking for stationary objects directly to the rear.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the X3. But it costs extra on the GLA.
The X3’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. A lane departure warning system costs extra on the GLA.
Both the X3 and the GLA have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, blind spot warning systems, rearview cameras, rear cross-path warning and available around view monitors.
The BMW X3 weighs 682 to 1151 pounds more than the Mercedes GLA. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.