I highly recommend APA! The academic program offers probably the most flexible and diverse set of options possible, with access to multiple universities, in-house courses, and self-study. The APA staff was incredibly helpful with all aspects of student life, really going above and beyond to make sure we were comfortable with our courses, host family, and general life in Paris. One aspect of the program that I really underestimated before coming here was the cultural program. Getting (essentially) free weekly tickets to shows across Paris was an amazing way to engage with the cultural side of Paris in a way that I wouldn't have thought to do or wouldn't have been willing to spend the money on (don't miss the shows at the CentQuatre!). The program offers a great deal of independence while still fostering a tight-knit community between the students and staff (especially through the group trips). My language skills improved a lot and I overall gained confidence and independence.
My advice to future students is to speak French as much as possible (even when only among Americans) and go out as much as possible! When choosing classes, prioritize scheduling and finding classes that seem manageable/ professors that seem chill. I'm really academically oriented, but go for the 3- (or 4-) day weekend - you'll learn so much from taking classes in French within a new system, so focus the rest of your energy on cultural and social opportunities! Also, just be aware that your host family (or other living arrangement) will almost certainly not be in the center of the city, and that you'll sometimes have long commutes to classes. This is just realistic and part of life in Paris, but it's something I didn't think about before.