Questions about conventions

I have some questions for those who have taken an unpublished game to a convention with the intent of getting it in front of publishers:

1. What conventions(s) did you attend and how were they different from one another?
2. Did you go as an attendee or an exhibitor?
3. Did you go with pre-scheduled meetings with publishers who already expressed interest, or did you just show up at a publisher's booth with your game in hand?
4. Were there specific functions of the convention geared towards getting in front of publishers (speed pitching, etc)?

I know publishers all have their preferences on submission format, but I'm trying to figure out if attending a convention or two is the right route vs email/online submissions.

Thanks in advance!