Love the artwork, i can't wait till the game comes out you've been working on.
I too am doing a few bits here and there for art but it seems to take me ages, I notice you said this took you 'literally' a couple of minutes. I was wonding what program you use or if you use some kind of hardware, plus could you say whether you use this on PC or MAC because of compatability issues...
I've heard of people use pad looking pieces of hardware and was wondering whether this is what you used seeing as it looks nice and sketch like without looking messy as a reel life sketch.
Keep up the hard work,
Madsman.