Almost everyone saved the going home during sims.

You'll know if you're struggling or not. They have clicker questions, post scores, you'll know inside if you're understanding it or not. Most people don't have many problems but some people do. I know how you feel about being worried when you hear guys failing out but it doesn't really happen often. The cases where that happens they almost always have something going on.

If you are understanding the systems and have a good background then feel free to go home. I always used the Friday night after the week to party. Saturday and Sunday I was with my group and we studied and went through questions/systems.

Find yourself a group to study with and fix up the systems that you don't understand on the weekends. Doing that, you'll be perfectly fine. Sims are pretty easy to go home, just don't be that dude who goes home and doesn't study a damn thing. You'll screw over your sim partner and you'll be the one looking real bad in the sim. I don't understand why some guys show up to sim expecting to be spoon fed the callouts and profiles....but even they still get through the program...