This is a great piece, and is done very well. You've caught the Gorillaz personality perfectly! One thing I'd like to point out though is that 2D is a vegetarian, so he wouldn't be even attempting to eat that hamburger. c: I don't mean to be picky or obnoxious, just constructive criticism. Other than that this piece is top notch!
I can't remember exactly where I found out that 2D was a vegetarian, that fact just stuck with me because I'm a vegetarian also. I would go on Gorillaz Wiki for basic information on 2D and the other band members, and just go on Google and find what you can. It took me a while to find out a lot of stuff.