If that could scale (and unfortunately my intuition says that it would not), that would be the first reasonable layout for a air/road vehicle that I've seen. Pretty wild.
It would scale just fine if you wanted to drive on the highway you would be stuck with a single seat aircraft because there would not be a lot of room between the blades. Also there is no need for huge wheels if you scaled it up. Worse, a helicopter is more efficient and simpler design and yet there a extremely expensive to fly relative to a fixed wing aircraft.
That specific design is not road worthy. Ideally you would want to be able to fold the top blades and add a duct for the pusher but that's not to bad. However, you can see the design is structurally fairly close to a car. Many designs have powered wheels simply for added maneuverability. Safety in a collision is going to be an issue due to weight concerns, but they can easily be safer than motorcycles which many people drive.
Advantages, unlike quad-copters loss of electronics or engine power at altitude does not equal death. They can do unpowered landings far more easily and safely than helicopters. Unlike fixed wing aircraft they can do vertical take offs and landings. Also there constuction and maintenance costs are well below that of a helicopter.
Downsides they can't hover, they have slightly lower top speeds than small airplanes, and unlike quad-copters they have a fairly large wingspan on takeoff. However, quad-copters are the only aircraft with this feature and there incredibly unsafe.
