the second one isnt very blended. the stock doesnt fit well with your render i guess.. but it just doesnt look right. also, the lighting is off as well. your light source in your bg is the left side, while his reflections on his helmet are top right.. also, the text is alright, but not good, if your gonna do that kinda font, try making it slightly smaller and blend it a bit more with the sig (thats all for the second one)
This isn't even constructive criticism. This doesn't even pass as an appropriate comment... As for the sigs, I think they need more to them. They're renders with some brushes or background behind them. In my opinion, the second one is better because the text isn't as distracting, although it doesn't blend well. But that isn't even Recon. It's ODST. Try new texts and blend them in.
They're both pretty nice, but the second could use some more blending even though I like the depth. I don't care for the text placement in the second one either.