Passed the exam last week. Exam blueprint provides pretty good information, I didn't encounter any surprises. ServiceNow recommends at least three courses:
plus two simulators ('CMDB Health' and 'Configure the CMDB', both included in the on-demand CMDB Fundamentals course) which makes sense. I don't think the exam itself is any more difficult than other CIS exams. But pay attention to the Blueprint (number of questions, item types).
These are courses you should do. If you have worked on cmdb then its not tough. Just go to new things offers by servicenow. Every course has quiz at the end. You will get idea how the exam will be. Best of luck.
