OK I will give you my perspective on the event from the West Coast Ariz version.
When my son went it was called the 16U championships, which has been changed to 17U now.
This was my son's first experience at a National level event and I don't remember exactly but think there were 100 something teams from all over the country. It is well run and there are college coaches from most of the major universities. I know my son's team coach was getting questionnaire's in advance to profile our team. We had coaches from many of these teams visit at one time or another.
The competition is top notch. I could not get over how many 6' something 180-210lb 16 year olds I saw. Some of the teams were frankly spectacular, and I was in awe of the level of talent at the event. We played a team from Dallas that still sticks in my head as the best 16U team I have ever seen!
You go to this event for several reasons. 1) To experience National level competition to see where you fit at this level. 2) To get the experience of a life time, one week of baseball with kids from everywhere can't be beat. 3) You get a look from the National team coaching staff, and believe me if you have the talent you will be looked at. (even though there is some pre-selection going on) 4) College exposure. It is there but it should not be the single reason to go.
I would go with a high quality team. This is important because it attracts the scouts and there is three days of pool play and then the top teams compete for the championship. You want to fall into the top group for exposure.
You DON'T have to go with an academy team but it IS important to be on a high quality one. My son's team played on the last day and placed fourth and it was not an academy team, it was put together by a coach who secured a number of top kids from our area. (So Cal) Nearly every kid on this team is either playing in college now or was drafted and is playing in the minors.
I believe the Fl event is similar, but maybe a bit smaller. My advice would be to go, not just for the college recruitment but for an experience of a lifetime, we still talk about how much fun this event was with kids my son sees as well as the parents.
Hope this helps.