I hit upon people reporting the firmware of the G-Box Midnight working like a charm on the Refee M6 device (f16ref).
Updates of the firmware/ROM can be found at:
G-Box | Software and ROMS
I installed the firmware dated 2012-10-03, it runs smoothly and it is rooted.
However you need to install Superuser from the Play store and update the su binary since the su included is a legacy one not asking for su permissions when running apps that need root access.