Problem with those is the same as the development of the helicopter. Helis solved it with a tail rotor to solve the torque issue, then the tilt rotor solved the forward/reverse/side motion issue. The military studied and experimented with flying discs in the 50s using fan turbines but control issues killed the project.
Colin Furze is a mad man!Love it! And it does work electronically much better than gas because its hard to control the throttle inputs fast enough compared to electric motors and a three axis gyro.
i was thinking if the fans could tilt it might help things , some kind of landing damper too , I guess he was trying to keep weight minimal to get some lift. But he is great he's the poor man's Guy Martin , I loved the jet bike .