Convenient because you can fly anywhere and through walls. People's commutes would be so much shorter! You could visit any country you wanted without even needing planes. Everyone would experience an unprecedented level of freedom.
Inconvenient because of the messy implications of getting stuck in walls if you turned it off at the wrong time. Also people would probably just be able to take anything they wanted without repurcussions so the world might devolve into chaos. You wouldn't really be able to jail anyone. Security and privacy would be hard to come by.