Having started this thread some time ago, my considered opinion (FWIW) is this:
Installing a detection/jamming device isnt worth the grief it will cause you if and when you're found with it. Having such a device will IMO be portrayed as "showing intent"... as in... only somebody who clearly intends to be speeding would go to the trouble of installing such as device. I'd prefer to be... innocently mistaken... than guilty of premeditation
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