In the very informative Fully Charged link (thank you J. Xau) the reviewer points out his test car has the “optional air suspension” that moves the car “down 40mm and up 60mm”. I don’t see this as an option however. I know the car drops down at speed to reduce drag - but I’m unclear if this is the same feature the driver is referring to - I believe the at-speed drop is standard. Any help?