i'm 15/15 at a wider stance. i'm pretty comfortable. little wider than shoulder lenght. i can do 360's on flat grounds with minimal pop. makes it that much harder vs if i had more air time to spin.
i'll have to take a video and upload for you guys to see...
One thing that is sometimes overlooked is that going very wide on a relatively short board can have some unexpected results. For one, there is less deck between your binding and the tip to flex. This will make the same deck fell stiffer in the nose /tail. Also, if you are even a little wide of your comfort zone, that can have a huge impact on pressing/buttering control.