Bowling for Columbine is Michael Moore's best work for me. However, I do not find, Michael Moore to be a documentary maker, he is more of a preacher.

I also think that he is one of those guys that are way far left.

But I  agree, Michael Moore has more credibility than Sean Hannity. At least, he challenges intelligently as compared to over the top accusations and antics. You heard of the NAMBLA accusation Sean Hannity made?