We did three of the boat excursions the Mnemba atoll snorkelling, safari blue, and Nakupenda with Prison Island. The three days were enjoyable but all the reefs we saw were dead. The fruit and seafood lunches were delicious. We booked through Rafiki hoping that it would make the somewhat chaotic experience of boarding the dhows more smooth but it is all the same for everyone no matter who you book through. We were also supposed to have a guided tour of Prison Island but we did not have a guide and we had to pay our own entrance into the island. Rafiki did reimburse us the entrance cost the next day but when we asked about the guide they said that it was not their fault that the company that RafikI booked with failed to provide the guide. We understand that things happen but as this was our experience we would recommend you book directly with the boats or maybe a different provider at a cheaper cost as there was no advantage for booking through this company.
Used them for a Airport transfer on Zanzibar, via Kiwitaxi, but you can contact them directly. The driver we got was VERY good, friendly and helpful, so I can only hope they just use that kind of people.
Amazing support. Pre and post customer service second to none.