Well,
I bought the three parts and I consider it money well spend.
I am halfway through the course and already Blender is making sense and you can work with the program on your own.
I had a question during one of the lessons and the author immediately answered my question.

If you work through these three parts and after that through the Underground 5 part videos, together with Greybeard's tutorials, you are well away.

Depending on how much time you have but if you have enough time yoy can learm Blender within a month.

Blender did not made sense to me, even after working through pdf tutorials for a long time, but now it is so easy. I can't believe that I have struggled so much earlier.

Regards
Johan