I would rate the first course a 3.5 if it were possible. For the price, I wish they had at least proofread the questions in the tests and elsewhere. Also, it was extremely hard to get through the videos due to the very heavy accents and unnatural cadence of the instructors. I resorted to mostly reading the sometimes incorrectly generated text below the video since the subtitles were often wrong (auto-generated and also struggling with accents) and would block the slides. I'm not exaggerating; I had to pause and see if the auto-generated subtitles could offer help in several instances. I really, really, really wish they had just used a text-to-speech program (free).
Content-wise, course 1 was a decently comprehensive introduction to robotics and mechatronics, although it was not always well-organized. That being said, some questions didn't make a lot of sense, likely due to a language barrier as well.