I work for Plasmart, the North American distributor of the Plasmacar. I am not pushing our product, just being honest. The Plasmacar is a higher quality more durable plastic. The How To Challenger, Coaster Car, Twistcar, Wiggle Car and other knock offs are sold are the grey market through website, often without contact information, kiosks at malls, fair and festivals. These are temporary situations that allow the seller to disappear after a few days. They do not offer any type of service or warranty. Should a part need replacing, they will contact us, since we are the only company that supplies replacement parts. Obviously, we will not sell replacement parts in support of these knock offs. The parts are reserved for Plasmacar customers only. So now you've wasted $40.00 on an item that can't be fixed and has to be thrown in the garbage. The Plasmacar is a little more expensive, but replacement parts are available for purchase which means that it will virtually last a lifetime.