I went to one in Philly back in the late 90's, when it was still more of a nerd-fest and not as popular as it is today. I was a casual collector at the time and went with a buddy of mine. It was more out of curiosity really than collecting. I think it was just a 2-day event. It was cool seeing some of the artists and stuff. I picked up a few things but nothing really expensive or noteworthy, save for one thing. I found a copy of MAD Magazine from June of 1971, the month and year I was born. Thought that was cool.
I don't recall spending a ton or money or anything, but that was almost 20 years ago. Oh, and I did get my picture taken with Mr. T too. So there's that.
I like looking at photos and reading articles about them nowadays, but I wouldn't have an interest in actually going to one now. I don't have the time, money or even comic knowledge anymore.
_________________
I used to be with it, but then they changed what "it" was. Now what I'm with isn't it, and what's it seems weird and scary to me, and it'll happen to you, too.