I think everyone above give good advice, but I suggest you to really understand the material instead of just trying to memorize them. Because as you hit the MCQ more often, you will start to click answers without even finish reading them, which is bad.
I did all the MCQs on Ninja, but for the missed questions, I made sure I reworked them multiple times and took notes, so when you hit your final reviews make sure you review those questions first. At the end of my final review I was trending 98%-100% with zero questions missed and 2100 questions attempted but I was only averaging about 76%(I believe it's due to I marked a huge amount of guess questions during the first attempt), but since there were so many stuffs within the BEC, especially the I.T portion can be really tricky in wording, I made sure I understood the structure of each I.T system and their limitations. I consider myself pretty tech savvy as I took some coding classes back then but I was shocked at the amount of craps I didn't know or should I say some of these controls or “roles” do not exist in real life, in fact I even passed some of these I.T questions to my company's engineers and they looked at me like “wtf?”. So don't underestimate them.
About memorizing all the formulas, I don't think it's necessary. But you have to know the fundamental such as CAPM,CVP,BE,MC,Variances,WACC,CPI,NOPAT,ROI,RI NETPV, EFU,etc. When I say understand them, I mean you need to know how to work them back and fore not 1+1=2. However, I do think I over studied the calculations and you might get an exam which give you just four or five calculation problems. I also recommend you to have a good understanding of COSO/ERM and ECON section since those sections are easier and shorter.
During my exam, I think the questions I received were very well diversified, I had some tricky ones, and took my best educated guess. Believe it or not I took the exam on the 9th and I still remember four of the questions which I thought were “bs” and they were six or seven sentences long and I spent at least three to five minutes on each. I had about 55 minutes left for my WC, and I don't know how I did it but I finished all three with 20 seconds left then walked out Pometric not sure of how I did. But today I found out I actually got a “stronger” score for WC and I thought I got maybe 8 points at most since English is not my first language.
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