First of all, I'd like to say that I'm not much of an Artist, so don't take my opinions too seriously. Wait for Snudge or Rizla or someone to come, and they'll give you a honest and REAL opinion.
However, I'd still like to throw in my $0.02, if that's okay with you.
I like the first one more. I don't know why, but the text and the girl in the second one just seem quite out of place. I don't really like the colors that much either.
In the first one, I think you should make your name a little bit darker and heavier, so it's easier to read. I don't know if you were intentionally going for that style, but regardless if you were or not, I think it still could be darker.
Just my opinion. But like I said, wait for some real Artist to come and rate you.
For the first one, 6.5/10.
Second one, 4.5/10.
Good job for your first try, if I may say so, and good for you for learning how to make your own Sigs.
