Can be a lot of work and difficult depending on your TA. I had Mitchell as my TA and he was awesome. He tried to make the time in lab as short as possible and his reading quizzes were pretty simple. If you don't do well on one of the labs, he offers rewrites. Also, he was super helpful during office hours or by email for both lab and lecture. The lab itself can be tedious and time consuming, but they are supposedly rewriting the lab manual, so it should hopefully be better.