Had a great experience with Elixir Divers. Went diving with them rather spontaneously on six dives (3 days). The team including the dive masters (Tomas, Kamila, Martina) and the boat crew were super professional. The made sure everybody was save and had a good time.
As this is the only dive shop on the island, prices are on the higher end; nevertheless, the dive spots make up for it with the abundance of fish. The team also does a full service job, switching tanks and preparing your equipment (personally I am not a fan of that, but I know some people expect it and it adds a layer of safety for less experienced divers).
Furthermore, they helped the girlfriend and me by organizing an island hopping trip on very short notice (night before). The trip was great and very well organized. Captain Bao (not sure if spelled that way) was just pure awesomeness.