We chose to do this pretty much on a whim. We enjoyed the train ride both up and back, but on both legs eventually we got a little bored. They do their best to keep you entertained with live music, coloring books for kids, tour guide/sightseeing stuff, snacks, photo ops, and so on. So the experience is fun, just slow. Taking the train is twice as long as driving, and parking at the park (at least when we went) didn't seem all that crowded. It also limits the amount of time you can spend at the park itself to around 3 hours, which isn't all that long given how much there is you can do.
So while I enjoyed this attraction, I would only recommend it to those who are going to be at the park/area for a few days.