Speed cameras are more about revenue raising than saving lives so I think it's fair to flash oncoming drivers.
Australia's speed laws are crazy but then again Australian drivers seem to be incapable of driving with the same skills as nations with much higher limits (keep left people, it's not rocket science) so maybe they deserve highway speed limits designed for people driving cars from the 40's.

Driver training seems to be focused on passing the test not learning defensive driving skills. I think that subsidising defensive driving course for young drivers might be a better way to spend money than campaigns that don't seem to work. Let's face it, most teenagers are pretty cynical about the messages that TV delivers.