I stayed at the Sankara Hotel over a long-weekend escape and checked into one of their junior suites. Although the suite's aren't really that big, I must confess that the small touches everywhere in the room really did make it worthwhile for me. The bathroom alone was in itself probably worth the extra money. The service was incredibly warm, attentive, friendly and staff seemed to anticipate your needs and were ready with suggestions or advice when needed. The club lounge staff were particularly impressive and helpful in assisting with various requests.The rooftop bar and pool has a very funky atmosphere and seems to attract quite a few of Nairobi's young and vibey after work crowd for a pretty good selection of cocktails. From the rooftop bar you can then head to one of the hotel's restaurants. Personally I enjoyed the Artisan Restaurant and sitting on its terrace enjoying the incredible Kenyan lamb dish.
The hotel is also perfectly situated being close to some great restaurants, bars and clubs and quick access to several shopping centres. My only word of caution in terms of its location would be to allow sufficient time to get to and from the airport as the Nairobi traffic is incredibly bad.
I'll definitely be returning there on my next trip to Nairobi.