The sniper's voice seemed a bit young and didn't fit the character very well, and if I may be nit-picky, the entire design didn't fit his job as a professional killer. If those were simply binoculars that he was looked though at the start, then everything would fit well. (Like he was some low-level gangster stalking the feller.) But other than that, the entire short was great, albeit it didn't last long enough for my tastes.
The animation is fantastic, and the story is simple, but well executed. While the rooftop set could use a lot more detail, the opening set was great. The "Scope-vision" was done decently, but the overlay seemed too simple and cartoon-y.
The ending felt cut-off, and unfinished... The after-credits scene helps to round out the ending, but I forgot to watch that far on the first viewing. This installment's main flaws are it's not having as much story/development as the others. The first one obviously introduced the character and most of his powers, the second showed his secret identity, but this one didn't really reveal anything more about him. There was also a lot less build-up to the action this time around. The music was a bit annoying, especially after the first viewing. ("Duh, duh, duh" repeated ad nauseam.)
I liked the aspect on not seeing Cheese Man very well for a while. It helped add a lot of mystery and drama to him.
You did very well, looking forward to the next one.
Advice for next time: Longer running time, more plot, more info on Cheese Man.