I'm unable to just "view results" so i'll just put down what i'm expecting to do at this stage
I'm extremely surprised how many people made there own.
Let's say it takes around 20 hours all up to make a bound ref,
that's almost 20 extra prac exams you could fit in! Surely spamming more prac exams is better?
If you make it as you go along, then you aren't really losing that time, as you are learning as you make the bound reference, and at that point in time, you aren't ready to be doing trial exams. Also remember its not how many practice exams you do, its what you learn from them. After each exam I would go back over what I got wrong, and see where I went wrong, if it wasn't a stupid mistake, as in if it was something that I genuinely didn't approach in the right way, I would make a note of it. If I did it again then I added it to my bound reference so that at the end I had a small list of what I used to go wrong with, and the mistakes that I seemed to make more than once. Then in the exam I used that as a kinda of checklist to make sure I didn't make the same mistake in the actual exam, ended up picking up one or two things and correcting them.
If you make it from the start of the year, you're essentially just devoting a maximum of 30 minutes each night and will have it done before you start trials, so that's not really an issue. 
When you have 4 or 5 subjects, then thats probably a little bit too much time for the bound reference, but then different things work for different people if you have the time (most likely won't have that much in yr 12).
By the end of the year I aimed to be at the point where I didn't need the bound reference, as someone has said before you need to do exam 1 without it anyway. (Also had my calc guide pasted in the back in case I forgot how to use the calc).
So basically what I'm saying is the reason that I made my own bound reference is because it was helping me learn (as I basically went ahead and learnt from the textbook for all three maths). Even though I pretty much didn't use it in the exam it wasn't a waste of time for me.