This place is especially great when the weather is not so good. Expect to spend a day and a minimum of $100 for a family of 4. Plenty of activities for kids, the available food is nothing great, it's mostly deep fried or hot dogs. Arcade games and huge, multilevel activity centers means kids cab have fun for hours. It can get very busy here, especially weekends. Lots of parking!
There are no real downsides here, the facility is clean and well maintained. There's plenty of staff but for the very little ones, the action can get a little nuts! Also worth mentioning that there are Uber drivers in the area. You can metro to Montmerxy and go from there, it's a 10 minute drive from the metro, a $10-$15 ride.
Planning parties is easy, you can do it online or in person and the prices seem high but may be worth it depending on your circumstancess. Have fun!