Pros: The quality is good, really good looks crisp and smooth. The sharpness is definitly there, and I think that it's brilliant. The render is good, though I can see a weird outline on his suite. I like the color choice on the boarder, blends well with the rest of the spray. The pop up effect gives your spray a good 3D look.
Cons: The boarder is too plain and simple. The render is kinda sloppy, and has a white outline on it.
Improvements: You should redesign th boarder, to something more thrilling and interesting, use some brushes. As for the render simply go to Layer > Matting > Remove White Matte, or an inner black stroke with about 60% opacity might do the job.
Notes: It's cool, keep up the improvements in mind.