I read the latest NZAutocar magazine the other day, the one with the FG Falcon on the cover. In the letters to editor section there were quite a few people unhappy with the decision to ban radar detectors. I've heard there is a fair bit of opposition growing around the country in regards to the law change, and that this law change would be repealed by the National government if it got into power.
The editorial of the Feb NZ Autocar refered to an overseas study that found radar detector drivers are involved in less crashes. I can't find the bloody thing for more info.