I had Ilia Kolmagorov as my instructor and I really enjoyed the course. It provides various helpful kinds of material including Shaan Patel's books, linear non-timed modules, timed practice tests (that are adaptive and as hard as the actual college board SAT), and hard math quizzes. All of these things make it so that no matter what you are looking for, Prep Expert will help you improve. I learned so many strategies from this course and I think it taught me exactly how to think when solving SAT problems. The instructor was genuinely really funny and enjoyable. Before the course, I got 1310 on my SAT, and so far I have been getting 1410 - 1460 on the Prep Expert practice tests. Prep Expert is also super responsive and immediately will solve any problems with the website with a quick live chat message.