To me it reads like the difference is that the wingsuit is meant for high altitude deployment, allowing for a greater range of operation but not concealable. It's jet pack also allow for movement upward, contrary to the Airfoil suit, which is concealable, and meant for heights up to 500 meters, and it's jets are just for maneuverability and speed rather than thrust upward. Both have distinct uses - however as a GM I would consider house ruling so both would use the parachuting skill.