For people who did achieve this, is it all hard work? A mixture of hard work and brains? Or is it all because of brains? 
You only get out what you put it, but I feel like I have put in so much. I know I haven't actually sat the exam yet, but after being on this forum for a little while, it seems to me that 99.00 is extremely hard.
So, people who have finished, JUST HOW HARD IS IT? What was your final year experience?
It's a mixture of both hard work and brains - though sometimes one compensates for the other, if you're naturally more gifted, then you won't have to work as hard as someone else who finds it harder to get everything straight off the bat.
No, you don't get out what you put in, what you put in is one of the factors which contributes to what you get out, but it isn't the only factor, how intelligently you work, as well as how well you can sit exams are other factors amongst many others which I won't be able to tell you.
It's not hard - just do what you can do, and you will get what you can get - that's the way I see it, the harder you make it out to be, the harder it will actually become. I found year 12 quite fun, just the fact that I was doing everything for the last time.
Like I always say, Year 12 is the first time you study for something more than just a meaningless number, it's not about your ATAR, it's not about what you get on your exams, it's about your pride, your future and you being able to reach your dreams.