I had a fantastic time in Santiago with COINED. I really liked my host family--they were quite kind to me and flexible with my schedule. If I wanted to come back late, fine. If went out to dinner, or wanted to eat dinner early, fine. I just told my host mom and everything was fine.
I went to lunch after class with my friends from the school at a variety of restaurants surrounding the school, then usually came back to the school for the activities, where we traveled around Santiago, checking out museums, houses, parks, etc. It was a great way to spend an afternoon and learn about Santiago. On weekends, I took trips to places we couldn't access in just an afternoon, and I made friends from some other schools in the area (as the weekend trips were combined with "sister schools").
The academics were great. The class sizes were small, and the teachers worked with us when we didn't understand. We read articles, spoke solely in Spanish, watched videos, and did exercises. I learned a lot and had a great time, making friends with the other students and my teachers in the process.