From my personal experience I have noticed zero off axis issues with the VP180. I have listened from the middle of my couch, the left side of the couch, and the right side of the couch.
If there are measurable differences between the slight off axis locations that I have listened from I definitely can not hear them under when viewing normal content. If you went extremely off axis perhaps things would be different but I am not sure. I have not done any critically listening from my far right loveseat. I have watched some TV from this location though and everything sounded OK.
I personally wouldn't worry about any potential off axis sound problems with the vp180.
