From Kia website... It should be better at staying in the lane as compared to lane keep assist since it uses the car in front of you along with the lines.
Highway Driving Assist (HDA)
Highway Driving Assist (HDA) is a driving convenience and safety system that reduces driver burden on highways and motorways by controlling the vehicle’s steering, acceleration and deceleration functions to maintain the speed set by the driver, keep a safe distance from the vehicle directly ahead, and keep the vehicle in the center of its current lane.
HDA uses navigational information to determine whether the vehicle is on a highway or motorway. When the vehicle is on a highway or motorway, HDA maintains the speed set by the driver or the speed limit of the highway or motorway. At the same time, it considers the lane information collected through its front view camera, and relative position and speed of the vehicle directly ahead computed using its front view camera and front radar, to control steering, acceleration and deceleration while keeping a safe distance from the vehicle ahead.