Honestly, I believe anything more than 90 is too much and inefficient.
I keep it around 60-80 mcq's per day and write notes for each question I did, explaining the main concept of that question. Then I go back and redo the MCQ's that I just did (should get a 100%). Then right before I sleep, I review the ones I did yesterday and today. My entire study cycle is 4 hours.
I really believe that you need to understand ALL the MCQ's you did and make sure that your brain is exposed to it several times before you move on to more MCQ's. I like to think its analogous to working out at a gym. You are not going to do 30+ different weight lifting exercises, 1 rep each, that use difference muscles because its not enough to make a difference. Rather, its better to focus on 10 difference exercises, 3 reps each and make sure you really get a good work out.
I also believe reviewing RIGHT BEFORE you sleep is essential. Supposedly, sleep is what consolidates memory (converts short term memory to long term) to long term, and thus, will reduce your need to ‘cram' a couple days before the test. Alternatively, if more of the material is in your long term memory, you will have more space/room in your working memory to ‘cram' other more important concepts. If you go to sleep with stuff you just learned, you have a much higher chance of consolidating it to long term/ medium term memory.
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