That first style ain't that bad. I like it. But on the first sig, get rid of the thing in the bottom right corner.
Lol Dizfunky, your too nice! The colors don't go together at all. The little thing in the corner of the first one is bad. Second render is overused. Effects behind second spartan are faded out too much. Glare on second spartan's visor stands out too much.
Actually, if you went to an art class you would know Purple and Yellow are complementary colors. The thing in the corner is a gun. It builds character. The only thing that I don't like is how you combined two filters or effects with on a really simple background. S' kay though.
No, Diz was correct. The color choices are fine as long as you like it. As for the signatures themselves, they seem a bit empty. It looks as if it includes two effects. Even with those two effects, the sigs are still nice.