For the joker one, I would try and make the background smudged all in one direction, instead of the random blots of colors. Concentrate on flow. Also the little black line around the render is a little distracting. For the sotw, the focal is a little blurry, sharpen it up a little. Also the text on both is a little boring. You should download some new ones.
On the Optimus Prime sig, I suggest taking the Noise>Pick overlay and setting either Blur>Gaussian Blur on it, with low settings, or putting a very low Gaussian Blur filter. Looks a bit too sharp, and the transformer itself looks a bit woozy around the edges. Maybe find a better render/stock, or sharpen that up. Good, but it needs some flow. Also, use Selective Gaussian Blur on the first one on a layer or two, it looks too Noise>Picked. But yeah, you've got a fine base to improve upon.
your joker sig needs to be cut better theres still a dodgy black line around the edges your SOTW just seems badly blured the rest of it is good
damn you're right, i didn't notice the line around it.. oh well, i'll try and fix it i guess and i'm gonna work on my SOTW entry, thanks for all the Cnc