can just see how safe it will be fiddling around looking for the emergency override switch as a semi-trailer moves into your lane How pissed off will you be the first time a software glitch (and let's face it, there will be plenty) limits you to 50km/h on a freeway
I believe the override would be something along the lines of puting foot to floor, according to whichever news was on tonight. And I know my GPS thinks theres a number of 40, 50 and 80 Km/h zones along the highways into the city and down to Canberra. Considering GPS has an average error of around 7m (assuming you're using the generic stuff and not the higher quality stuff used for geology/surveying, etc), it could indeed be dodgy when travelling along a highway that parallels another road such as the M7.
Still, all this is better than the idea they had a few months back of simply using them for monitoring. When you sped, it simply dobbed you in and you had to explain yourself. Now that was revenue raising at it's finest.
If they do come and become widespread. I wouldn't be surprised if before too long, they not only become mandatory on all new cars, but it becomes an offense to tamper with them in anyway. And of course there's the privacy question of what kind, if any, monitoring would occur of your driving and who has access to such material and for what purposes.
i'm all for it. When the road toll doesn't go down due to the use of these things, they wont be able to claim that speed is the root of all evil any more, and we might actually see something useful like ummmm.... actually teaching people how to drive
We can only hope. But alas, it is all too easy to see what you wanna see in stats; I don't hold my breathe.