Hey Bsulli, having recently taken most of the most recent tests (including 72 ... , unusual games in the 2 most recent tests, and a few ... />
I'd say the mostimportant thing is getting your brain ...
It varies a lot between people. The mostimportant part is to properly review so that you don't make the same mistakes as you did before. I would definitely do at least 20 if you have the time.