I just got back from the Montage Mountain waterpark two days ago, and enjoyed myself pretty well. The rides that were there were well kept, as was the entire park. The park looks to be only a few years old, and it's great because not many people know it's there. We went on a Tuesday, so there were no lines for any of the slides longer than 5 people. The only disadvantage is, there's not a ton to do! If you are going during the week, the zip line is not open. It's not stated on the website, but the zip line only opens on weekends. Also, there's only 5 waterslides all together, which isn't too many for a waterpark that charges $26 a person (after tax). Overall, I was impressed with the cleanliness of the park, and the lack of people. But if you are a thrill seeker like me, and want a bunch of rides, this is not the place for you. I would return if the tickets were a little cheaper, or if they expanded further.
If you own or manage Montage Mountain Waterpark, register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.