It is not like you have a wrong choice. Here are just some differences and similarities:
1. Floors: all Jambo DVC are on top 5th fl except for concierge right above the lobby which are on the 6th fl (that is the only area where there is a 6th fl). At Kidani, all rooms are DVC and thus all floors (2 through 5) are available. For savanna view, some like the higher floor, looking down on animals, and some the lower floor, looking directly at them.
2. Room size: studios are about the same size in both buildings; 1BRs (and thus 2BRs) in Kidani are much larger than Jambo and the Kidani 1BR has 2 bathrooms. Also, Jambo has a combined tub shower arrangement in the master bathroom and Kidani has the separate tub and shower
3. Pools: Jambo's is larger and has lots of shaded areas due to mature trees and bushes; also has two hot tubs, Kidani has one; both have zero entry area; Kidani has significantly longer pool slide; it also has the elaborate kids water play area close to the pool.
4. Restaurants: Jambo has table service (Jiko), buffet (Boma), and counter service (Mara). Kidani has only table service (Sanaa). Sanaa has nice views of the savanna; none of the Jambo restaurants have views. Jiko, Sanaa and Boma are excellent restaurants; Mara is good counter service.
6. Store: Jambo has the much bigger store.
7 Lobby: both are impressive but Jambo has the much larger lobby.
8. Parking: lot is away from front of building for Jambo; Kidani is ideal with parking on ground floor under the building, and with multiple elevators along wings you can always park near where your room is.
9. Busses: park busses stop at Kidani first, DD at Jambo first; at rush hour in the morning can sometimes hit crowded bus to a park if getting on at Jambo. Otherwise, bus service is generally good.
10. Walk to room: at Jambo you can have quite a long walk from lobby to room if at the end of the wings. However, Kidani puts Jambo to shame in that category and you can have the never ending walk down the endless hallway to nowhere to the end rooms (end rooms on north wing of Kidani are over 1/4 mile from the lobby and I guarantee you have never been to a hotel where the rooms in a single building are further than this from the lobby). Wise to request a room close to lobby there. At both, most things of importance -- restaurants, store, bus stop and pool -- are close to the lobby although the Kidani pool is more a little north of the lobby.
11. Room decor: comparable in both; whole resort has rooms-on-a-savanna feel; rooms are actually not very brightly lighted as internal lights do not go to real bright. In fact, whole resort has dim lighting that gives a sense of close to dusk on a savanna.
12. Savannas: Jambo has three: Arusha in middle of building, Uzima to east of building and Sunset to the west. Most Kidani savanna rooms look out at Sunset, the largest savanna, but it also has a small one to the north/NW , Pembe. Pembe has no giraffes, others do.
13. Distance between resorts: you can use amenities, including pool, at either building while staying in one. However, walk from lobby to lobby is about 1/2 mile.
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