I haven't been to KCon but I have read a bunch of blogs and accounts. The past years have been messy but they predict that this year should be a lot more organized. Be prepared to wait in lotsa lines. Its a convention- lines are a big part of your day. I also suggest not eating at the convention because it will be super expensive. And if you want Korean treats just go down to K Town which is on the other side of Downtown and it's nice. There are also so good kpop merchandise stores down there. And as far as merchandise at the convention I've been informed that you should pre-order. And I believe this is probably easier because I know when I went to see U-Kiss in SF, the line before the concert was long and they ran out of things like light sticks after the concert. (Light sticks are fun you should buy them lol). Like I said, I haven't been to KCon but I have been to that venue and to other events similar so I hope this helps a little. :)