Well, up until now I've avoided watching any Iraq war related movies. The Hurt Locker was the first Iraq war movie that I decided to see. I liked the film because of the way that it was shot and the fact that it focussed on the hazards that the men faced. The shooting method really made the audience feel like the fourth member of the team and the emphasis on the day-to-day activities that the men face was, to me, a departure from your standard war movie. Saving Private Ryan also does this, but SPR still manages to send the message that fighting WW2 was still a noble effort. THL didn't project whether the Iraq war was a noble objective or not. It just said there's the war and this is what these guys face in dealing with it.
Generation Kill is a lot like that too, but as you watch the series it definitely starts to seep in what a fucked up mess it was and is. So far, I'm leaning toward GK being better than THL in the long run, because it actually does tend to make a statement about what a poorly executed mess the Second Iraq War is. Also, the characters in GK are just more developed; although, a seven hour series does give immensely more room to do that type of development than a two to three hour movie does.