I'd like to know the final verdict on the EmDrive (or EM Drive); does it work or not?
Some say yes, others say no, some say the measured effect was not propulsion, but just the energy radiated by the cables.
Lacking any sound theoretical or unambiguous observational reason to think it works, it is about as likely to work as any other conglomeration of RF electronics assembled without any understanding of physics.
: Look at Shawyer's concepts on http://emdrive.com/hybridlaunch.html. He claims the EmDrive becomes less efficient at higher velocities (not relative to anything, but absolute velocity), and so uses it for "static thrust" because he believes there's something different between hovering above Earth's surface and accelerating at 9.8 m/s. He must have slept through the class where the equivalence principle was explained.