I know there are threads for this in the general forum, but they're mostly americans and i'm wondering about these products specifically for australian driving, thus i thought i'd post in here.
Firstly, are they at all legal in australia? I don't think they are, hope i'm wrong.
Secondly, do coppers have any way of detected whether you have a detector or not? Some time ago someone told me that cops reverse the detecter in the cop car, and then the detector becomes a detector detector.

hope that makes sense. Basically by the slight modification the cops can then detect who has detectors in their car. Is this right? Does anyone know anything about this?
Thirdly, how effective are they? Eg would it beep driving down alexander parade (melbourne folks) coming to that intersection with the duel speed/red light cameras? west gate bridge?
Any feedback appreciated.