I'm currently watching his General Relativity videos along with the MIT stuff. There's a really good explanation of vector co(ntra)variance and tensor algebra at the beginning of that course which I needed. And contrary to the sibling, I really enjoy his presentation style which assumes that I am not a graduate student in math who lives and breathes abstract algebra.
I've struggled to watch more than a few hours. He might be brilliant, but his presentation style is atrocious. He gets distracted, forgets things, etc...
Feynman's lectures in comparison are much more focused and sharp.