I would argue that the 2nd tests' effectiveness depends largely on the amount of time that you commit to your routine. If you are only studying for ~1 hour a day, it may be more effective to rely on the one, review the answers the next day, and drill/section the rest of the week. If you are studying for several hours per day, I think full practice tests will help. Half of the LSAT's difficulty (for me) relies in the simple fact that it's a test. For me, full-practice-testing helps because I have a trend of losing accuracy as time dwindles. If you share that similar trait, it may be helpful to take multiple preptests per week. However, preptests are a limited resource, so manage your time well. Good luck for august!