Agree that his Youtube content is great, I think the skepticism is about whether or not having a cool Youtube channel translates into being good at teaching an engineering course. I hope it turns out to be something that's great and worth the money, but if I were a betting person, based on my past experience with a lot of on-line courses, I'd bet it's not. It's unfortunate that in order to tell if a course is actually any good, you'll have to invest a considerable amount of time an effort before you realize it's not any good. I've wasted so many hours into bad courses that I have to wait until one is recommended over and over again before I'll give it a chance.