Hmmm. Hard choise for me
8 - Nice one, but not really may taste coz the left side is just too much black/dark, but i give you 2pts coz the rest is very nice.
6 - It would be nice but too small and horrible quality, dunno how did you make it that bad quality, maybe you should try to resize it or smth if you saved the .psd file coz it would be a very nice work i think. 1pts
7 - Idea would be nice but no "contrast" between the background thingy and the guy with the gun is barely visible this way. Some color changes on the background would make it better for my eyes.