Out of the hip-hop movies I've seen, this is definitely up there as one of the best and well researched,
drawing from interviews with quite a few of the actual legends.
The main question you're probably asking with this documentary is-
how is this any different from the book How to Rap
that came out a while back,
because that has 104 interviews with rappers (this documentary just has 47), and has a lot of the same people,
but even more and that book goes reeeeeally in depth... so does this documentary add anything new?
Well, the good thing is, this documentary is like a companion to that book, as it has a few different people and of course you get to see the people rapping freestyles to the camera, on screen.
So is this new ground? Not really, but it's nice that it was put together and it's definitely a welcome additional for anyone who is into the craft and taking an in depth look at the way hip-hop music is put together, rather than just the celebrity glitz and glamour that people normally focus on with hip-hop.
So yeah I would recommend getting this, good work.