I think doing passages is the best way to get better. Sometimes content review can just become redundant, and then you start thinking that you know everything.
If you do more passages, you will get more practice analyzing data, graphs, etc. and might get hit with a surprise question that tests content that you think you know. Then you can go back and see if you need more practice analyzing data/graphs--but the best thing is that it can pinpoint you to a certain content where you might have overlooked weaknesses.
Good Luck!