I know someone (not us lol, but a close friend) who was caught doing 60+km over the speed limit. He was fined a huge amount, given a few demerit points, AND lost his licence for six months.
I think he was lucky. A friend's kid was caught doing something similar, but in Victoria, and his car was taken as well as losing his licence, a court appearance, a fine, and I think he had to take some road safety course (or something).
Both guys were lucky, because their irresponsible, arrogant speeding could've killed someone.
Not everyone is guilty as charged, and if you aren't guilty, then argue it. I'm a bit cynical because I doubt you'll get far, but you can try.
If you want to speed, go use a race track. If you don't, and you get fined, then suck it up and pay.