Should I stick with the ACT or switch back to the SAT?

I think I’m just going to take the SAT again. I already have a big practice book, and my gc was able to get me a fee waiver easily. I’d rather not have to study for both tests. Especially considering I have to keep up with my school work, deal with college applications, and I actually want to have a little fun my senior year and not overstress myself too much.