Do you think it's better to hit the books till late on the night of an exam and have a maybe not-so-fresh brain full of knowledge, or go to bed early and have an alert brain that might be missing all sorts of key information?
I was the master of buying a 2L bottle of Coke at about 8:30 at night and studying right through to 8:30 the next morning, going to the exam at 9 and regurgitating it all, going to the Unibar for a mental (and sometimes stomach) purge and then crashing in bed the next night before doing it all again until exams were over.
Worked perfectly for me and I have the 4 Fails, a Pass conceeded and a Pass terminating and 3 or 4 marks below 55 to prove it. Got the bit of paper in the end though.
Only way to really know it is to try it. Otherwise past papers are a goldmine. Get your hands on them somehow (if there is a residential college on campus become friends with them because they will have the old exam papers) and just do as many of them as you can and you will be fine.
Me, I've got my Advanced Firefighter exam on Thursday night and can only find 1 of the 7 workbooks that I was given to study. Might be heading to the station on wednesday night to score the rest and set up a bit of last minute cramming myself.