This course disappointed me a bit after first two courses of "programming in scala" specialization: turns out good old for loop with mutable vars is much much faster than for expressions and that we threw check style out of the door and our code is much less pretty after all. Well, I guess that was a good lesson: there's functional programming, there are times when we can use it, and there are times when we need all the performance we can get out of our hardware.
In terms of lectures and assignments they were average in my opinion, I would actually rate lectures higher than in the previous courses and assignments lower. I especially liked lego analogies to explain how different types combine together, material on parallel collections and combiners (though this last lecture was a bit hard to understand and assignment was lengthy and didn't re-enforce material enough, so by the time I finished the assignment I already forgot much of what was taught in lecture).
Overall, my engagement was average but I appreciate an ability to use an autograder for the assignments without purchasing the course.