I seem to have watched a different movie from the one described in the previous comment.
The Delay story is a bit complicated but it's important, and I honestly can't imagine how it could have been better told (or how anyone could fail to find it interesting).
You do have to understand at least a bit about our system, and the movie does a great job laying out the info you need -- about Texas campaign finance law, the fact that the State legislature controls Federal Congressional district boundaries, the relationship between the U.S. census and political gerrymandering, the way gerrymandering in turn affects the composition of the U.S. House, and how corporations benefited from favorable Federal legislation as their quid pro quo for contributing to State legislative campaigns.
Explicating all that is something most of the media hasn't even attempted. But "The Big Buy" made it all rivetingly clear.
And with lots of footage of personalities like Tom Delay and Ronnie Earle speaking for themselves in their own colorful terms -- personally, I found it richly entertaining.
Regarding the aesthetic surface, I think it's fair to point out, this was probably NOT a big budget operation.
The important thing is that the filmmakers nonetheless managed to get hold of tons of important information, to analyze it thoroughly, and to shoot and/or get hold of TONS of great footage, all brilliantly edited.
I hope a lot of people see this film. It could greatly help us all gain a more sophisticated understanding of how our system is -- and is not -- working