Have you actually run one of these units alongside TAS?
Are you certain you know the "ghost" traffic is "ghost" traffic?
What is a TAS?
If you mean TCAS, yes. If you mean radar, yes. If you mean something else, then you'll have to explain.
Am I certain the traffic is ghost traffic? Yes; particularly after using infrared and night vision to search in the same location as the traffic indicated on the Xaon unit, as well as tracking and updates with threat radar.
How have you actually assessed for any reasonable period of time that these units are beset with an unreasonable number of errors?
Depends what you mean by any reasonable period of time. If you mean 20 or so units over about eight months and several hundred flight hours, yes. If you mean something else, probably not.
Possibly because comment is based on the usual irrational and unsubstantiated observation.
Oh really? Pray tell.
Turn the transponder off and see if they disappear.
That was certainly done, as well as the involved assistance of several expert avionics technicians. No improvement.