It's pretty good, although I cannot really read the text and I think that Zack could be a bit bigger.
I really like it! Making Zack small and having the color overlapping him a bit, makes it look like he's fading away into mist. ^^ Overall, it's a nicely done, emotional sig. *give kudos*
its so-so but you should try enlarging the text and add in some effects to get some flow into the sig.