We stayed 2 nights at the end of our 9 days on Zanzibar. Mustapha's is quirky and laid back. The grounds are so welcoming we spent most of our stay just relaxing in the compound--reading in the hammocks, playing cards while enjoying a drink, and eating their delicious food. The beach is a quick walk away and is very quiet. There's quite a bit of seaweed right near Mustapha's and we ended up walking about a quarter mile south to swim in clearer water. We were only there one full day and wanted to relax so we didn't explore the area much. Bicycles seem to be the preferred mode of transportation and Mustapha's could rent them to you. The compound was always full of happy people, most of them young backpackers full of lively conversation. Regae music added to the atmosphere.
We had a room with a private bath and hot water (Hickman). It was nice with a huge mosquito net but the fan wasn't really up to the task of working up a breeze. If I had it to do over, I'd probably spend less money for a room without a bath since the extra humidity of the bathroom contributed to the stuffiness of the room.
The service was friendly and accommodating. We had to leave before 6AM for an early flight. When I asked if we could get a banana the night before since we'd miss breakfast they offered to get up early and give us breakfast so we had the full plate of fruit and juice at 5:30AM (we didn't have eggs--that would have been too much to ask for).
There's no wifi, but we didn't miss it.