If you want to be in the middle of all the action, this is the wrong hotel. However, if you want to get away from it all, and completely relax, Cerf island is a great place for that. It is also a great base from which to explore the marine park and the other islands in it. The hotel has free kayaks which are worth taking advantage of. They also offer free snorkel gear. The snorkeling isn't great in most places around the island, but there are a few gems that the hotel can point out which have an amazing quantity and variety of fish.
The rooms are just ok and the bathrooms could really use an upgrade (or at least some maintenance and a lot more light), but you don't come to this hotel to sit in your room. The balconies and patios, with views of Mahe, are a great place to unwind. The food at the restaurant is just ok. Nothing special, but filling. There are no stores on the island and the hotel only provides bottled water on the first day, so be sure to stock up before coming to the island. The boat transfer from Eden Island was decently convenient, except that there is no late boats so you can't have dinner on Mahe.