Best competition of the year in my opinion, as you can get really close to the dancers. Wed is amateur latin and pro ballroom, Thurs is amateur ballroom and pro latin. Evening sessions (final rounds) are reserved seating, but you can sit anywhere in the day. Get there early and you could even get floor seats.
I think Thursday is the best day/night, but I'm biased as I love pro Latin. I'm sure you'll have a great time if you do go!
For sure my favourite competition of the year, and I go to pretty much all of them. The only one where you can reasonably still expect to be sat floorside when the big boys come out. I go for all of the days but for me also the Thursday is the most important.