It took me about 2 weeks. I did not like it at first. But, once I did them at 1.5X speed and really listened and took notes I started to like it better. Some of it is corny but I thought it was a good review and I needed that. IF you are near the top of your class and start near a 230 then it is not really that helpful for you. It is made for us that did not get it all the first time and need a review. So if your first test is around a 180 then it will help more.
Lastly, I found it definitely helped me connect dots faster and remember things. Also, it helps me get through FA faster and easier. I remember them talking about it and going over like I do in class. It is how I do class so it works for me. I listen to lectures and then do the powerpoints.