Some footage from a quick flight with mine:
I am getting a big difference in color balance between the center of the image and the border, as well as some visible vignetting. I'm attaching a screen grab of what should be a fairly homogeneous landscape. It was a mostly cloudly/overcast day, so the lighting is pretty even.
When you look at samples from different areas in the frame, however, there's a big difference. I'm also seeing a difference is sharpness between the center and the rest of the frame.