No, not seen it myself yet. Just been looking at all the newer movies on their way and this one came up.
I watched BOWLING AT COLUMBINE where he confronted Charlton Heston.
I have read denunciations of Moore, saying that his documentary personae is in stark contrast to who he really is and that he is just as corrupt and elitist as the people he hounds, but whether that is true or not he is certainly braver than I in taking on idiots with guns - who tend to fire first and think last.
Truth be told, I keep expecting him to come to a sticky end at the hands of some lunatic, sadly.