<p>I hear the main advantage is that you get a little more individual attention and you get to work in small groups during class periods. This approach is useful for people who aren't really confident in trying to master calculus on their own, but many people are just fine with studying math on their own. It seems like the workshop program is also fairly structured so it will ensure that you don't get too behind, which is often what hurts students taking calc. </p>
<p>This website shows how merit students on average do better in merit sections compared to students in the regular sections, but you have to consider the fact that there are certain students in the regular sections just completely slack off, which inherently brings down the averages. </p>
<p>I think the main thing to consider is the type of learner you are. If you can learn well on your own, then the merit workshops aren't really worth it. Plus, you need to decide whether the merit section is convenient in the overall scheme of your schedule.</p>