The primary purpose for taking a practice exam is to figure out what your strengths and weaknesses are right now, so that you can use that information to develop a study plan (or to set priorities, if you're working off of a syllabus) to last you until your next practice exam. As you've probably noticed, the syllabus includes quite a lot of homework, but your needs aren't the same as every other test taker's needs—you'll need to prioritize based on your own strengths and weaknesses. So, yes, definitely analyze practice exams right after you take them.
It's also the case that you don't want to take an exam every week (I don't know how often you're taking them). Earlier in your studies, you're going to be going 4 to 6 weeks before taking another exam, because you have a lot to learn for the first time before it's worth it to take another exam.
Later in your studies, usually after you've been through your study materials once and are reviewing and deciding what needs more work, the timeframe will shorten to something like 2 to 3 weeks before you take another exam.
In our program, we have you take one exam at the very beginning, and then just two more over the length of the 9 week program—one at 6 weeks and one after you're done with all homework from week 9.
Use this article series to analyze MPrep exams:
https://www.manhattanprep.com/gmat/blog ... ts-part-1/As you noted, it takes a long time to analyze a test, so build that into your study time. I'd generally plan to spend the next 2-3 days analyzing a test (after taking one). For the very first exam at the beginning, you don't need to do such an in-depth analysis. You really just want to get an idea of your overall strengths and weaknesses to help you set priorities as you begin your studies / until your next exam. But once you hit your second exam, yes, do the full analysis described in the above article and then use that information either to continue to prioritize from the main syllabus or, once you've finished your syllabus, to figure out what you want to review or study again to help lift your score further.