We stayed at Hakuna Matata for three days, flying in from JRO after a safari. Arrival was a smooth process (we opted for the airport pick-up), and a welcoming refreshment was a nice touch during the registration process.
Overall - everything about Hakuna Matata was excellent. The rooms (small bungalows) are nice, but with a beautiful beach and all the other attractions of Zanzibar, you won't spend much time in your room. Only issue I had was trying to figure out the air-conditioning controls. The staff and management were all quite friendly and welcoming - and I particularly liked how they had organized a beach dinner (with live music) on one of the nights.
The beach was great and the water warm (February): we liked how the HM part of the beach was nicely maintained, and low tide was a great opportunity to explore, chase crabs, and walk down the beach.