I took it about 5 years ago. Its all multiple choice. I was able to pass it without ever seeing a JAMF instance before just by going over the study material. If memory serves me right, the practice text and the exam were pretty comparable.
Dont forget the JAMF Exams are open book, just keep your notes up and command+F the key terms. Its kinda hard to fail as it is targeted at entree level helpdesk. If you have access to a JAMF instance even better as you can go to what its talking about to see what your options are, like can you export a report as what format?