Excellent! We loved this day trip. Our guide, Christian, was really interesting and kept us engaged throughout. We visited the freshwater pools (known as 'eyes' by the original inhabitants) where he taught us about the local wildlife and how various plants were used for ailments, food, poisons etc.. We also saw the iguanas and turtles at the reserve and swam in one of the crystal clear pools. It was a great experience and one we would recommended to anyone visiting the Dominican Republic!
It was a good excursion. The guide was very knowledgeable and it was just us on the tour so we could ask as many questions as we wanted. The lagoons are truly beautiful and you can swim in two of the 12 we saw. We were also able to be in the lizard pen since it was a private tour. We felt very safe. If you only want to see one or two lagoons there are probably shorter trips without the scientific facts. Vivator was very professional, send us reminders of the booking as well as copies of the reservation. You should know that the pick from the hotel had a SEGWAY tour car and shirt so we almost did not go with him. Make sure you confirm when you are coming back though. We were done at 11:30 and they first offered to take us to the beach until 3, then they said we had to stay there until 1 when the Segway tour was done because their other cars were not available. It was our last day and we wanted to get back, so I finally offered the guide an extra $20 to get us home fast - we left at 12:15!
The Lagoon is extraordinary and well worth it. Our guide, Matteas, was also great. However, some things to think about: The shuttle picks up at multiple resorts - ours was first, so it took us an additional 30 minutes to get there we paid for a private taxi on the way back. Also, the tour of the property is just OK. We found the history of Punta Cana fascinating, but didn't need the extra time seeing the farms, iguanas and sugar cane. I expected a bit more context and information - it was eco-tour : light.