Does it really work? You just spray it on the plate?
I have heared it does work, have yet to try it. Have you seen those license plate frames that are chrome or those lovely cds hanging on view mirrors, appearantly they deflect either the lazer or radar not sure which just heresay.
Better yet, go faster than the camera reaction time. Mythbusters tested a speed camera once and found they're not functional for objects travelling over 120mph.