I am sure this place is fine for older kids, but after leaving our three year old there for two hours, I would not recommend.
Our three year old was in the same barely supervised play area with all of the older children. When we arrived to pick her up, we saw her get into a slide, get scared, and cry/beg for help. No one even turned around to see if she was okay. It actually took me telling two people up front that she needed help before they finally went to check on her.
Not impressed.