what is the use?
it may be cheaper than cars (the gas, to get these would probably cost tens of thousands.) but the travel would be 100x more uncomfortable. (The higher you are, the colder it is, you also have to use physical strength to actually flip the things to get anywhere and that would exhaust anyone extremely after a while). To counteract exhaustion, you'd have to make the wings much larger so you can balance the weight and the wing power. But since these things are loving gargantuan, you'll never be able to fit through a doorway again. you'll sit down at a restaraunt and take up the entire room. There's no 'hiding' these things, they're organic material, they don't just retract when you don't want them.
They seem completely pointless.