I haven't been but my friend has, only the one she went to is in Boston... she tells me all about it and yes it is definitely worth it. Get the tickets while you can, I'm most likely going next year, and save up a bunch of money if you really like anime and want souvenirs. There is everything anime listed there and a few people who do voice acting for some of the anime characters, so if you want their autograph then go. I don't know how yours is though, but I'm sure it'll probably be similar.