Nati completed this course, spending 8 hours a week on it and found the course difficulty to be hard.
Easily one of the best courses I've ever encountered. It is difficult for someone who is not familiar with FP but in a good way. You learn a great deal as you work on exercises, which are, by the way, very thoroughly prepared.
I must say, however, that setting up a different IDE than the suggested Eclipse was a pain and course does not cover the environment or its troubleshooting. Discussion forums thrive with such discussions, though.