We stayed at Agua Vista in April 2009, never having been to the Montezuma area. It was a perfect choice for our family (my wife, two daughters (7 and 9), and me).
As others have mentioned, there is a long and bumpy driveway up the hillside to Agua Vista, but, once there, you realize it was well worth the time and bumps. The house we stayed in was simple but very nicely furnished and equipped. The views are incredible from the patio, which is where we spent most of our time while at the house. Our house had a small private pool, which was perfect for quick dips to cool off.
Alex and Khalida are wonderful hosts, stopping by to make sure verything is OK but not intruding on your privacy. They also know the area very well and were a great help in setting up day trips (zipline tour, boat and snorkel tour, etc.) and recommending restaurants (Cocolores was our favorite).
Our daughters loved everything about Agua Vista and the area, especially the outdoor shower, the monkeys and other wildlife right on the property, the short hike from Agua Vista to the waterfalls and diving hole, and the zipline tour just south of town.
We'll definitely stay at Agua Vista when we go back to the area.More