I attended FDIC from the first year they moved to Indy in 1995 until 2008. I had the good fortune to participate as a Hands-On-Training (HOT) instructor for 9 of those years. A well run organization.
Definitely worth attending. And most certainly much larger than any conference held in our country, by a long shot.
Check out hotels a little further from downtown. A pain to have to drive in 15 - 20 minutes and park but way cheaper than $300...