“The results of NASA’s tests on the ‘impossible’ EM Drive have been leaked, and they reveal that the controversial propulsion system really does work, and is capable of generating impressive thrust in a vacuum, even after error measurements have been accounted for.”
This is propulsion without fuel. Mars in 70 days instead of 18 months. No bulky fuel tanks marring the design of your space vehicle. Moreover, no explosive fuel to worry about. Leaving the problem of shielding from cosmic rays to be resolved, but with considerable new incentive to do so.