I think 4 days would be good, if we had a like a day zero like thing. Like if we had enough industry people, and press people come, this would be the day that they could host their press panels, and then people can pick up their badges and press could get what they wanted from the guests. I would say it would be like half a day. However, as of right now I don't think 4 days would be good. NDK isn't that big, in the grand scheme of conventions (for example AX2011 had approximately 50,000 attendees, and Otakon2011 had close to 32,000) NDK is barely breaking the 20,000 attendee mark (and that is just me estimating with the attend cap). Don't get me wrong I love the idea, and my ideas could run wild if we did of what we could do, pre-con wise for it. On top of the other reasons, I don't think Nan Desu Kan is ready for a 4th day.