I assume some here have taken or are currently taking a Udemy course. Any thoughts on your experience and the quality of their course(s)? What courses did you take?

It hugely varies, i once had a java course which was pure design (drag and drop with gluon scenebuilder), was kind of really annoying. I could have figured most of that out myself. It was highly rated, but i strongly disliked. But usually there courses are good/very good. Given everyone can add courses, you will end up with huge variety in quality.