Tested and fully functional on the currently installed firmware (03.53.3.0), with normal signs of use and scratches.
If you plan on updating these to the latest firmware, please read:
If updated to the latest release (3.62.7.0) and operated in Dual2K mode, these units will freeze at the status screen after a hard power cycle.
If you encounter this issue, power off the unit and remove the SDI mezzanine card. This will force the unit back into Standard mode, allowing you to install an earlier firmware version.
I am unsure whether this is a hardware or software fault specific to my units, but the issue was repeatable on all four Dual units I own.
The lower price reflects this issue.
Again, this problem and solution are only relevant if you both update to the latest firmware and switch to Dual2K mode. With the current firmware version installed, this unit is perfectly functional, even in Dual2K mode.
Very Strange ¯\\_(ツ)_/¯
If you know anything about this issue or have any questions, feel free to send me a message.