people say multiple choice is dumb, and I agree, we'll have to do lots of working out for one mark, which is not worth it.
....lots of working? ...on what appears to be pretty straightforward questions. Most of those sample questions are only ever worth a maximum of 2 marks, maybe 3, 1-2 mark for the development of the solution, and 1 mark for inputting the correct values and finding a solution.
And even if you do get them wrong, in the HSC, you will lose that mark for the incorrect development, and get a mark for the working out. So really, you don't lose anything. Say if one of the MC questions was actually a 1 mark question, and you do the working but you make an error, you lose that mark, period. So, either way, it's the same amount of worth as what was happening, which is why I find it pointless and not making any difference whatsoever.