You never cease to amaze me dude. I agree with ~discodann though. He looks to centred. I think it would olook better if he was a little rotated and coming in from the side. Just the main part of his body though. Keep the rest where it is.
Although the center body of the sentinel is way more simplistic than the real one it would be sufficient if you placed several in a scene and the camera was farther away. It sure looks like a lot of work went into that. 3dsmax??