Palacina is a great choice in Nairobi. At first, my girlfriend and I were a bit reticent because it was more expensive than other options in Nairobi, but in the end we were very happy we payed the slight premium.
The hotel is extremely safe. The rooms are comfortable, clean and tastefully appointed. We were on vacation, so were happy to see that the hotel definitely had a Kenyan flare and didn't feel to sterile. Perhaps the most impressive is the superb customer service: super welcoming and accommodating staff.
A couple other notes:
We organized an airport pick up with them, I recommend this instead of a taxi or other car service. Driver was waiting right outside immigration and provided an extremely pleasant ride to the hotel.
There is a restaurant on-site which is decent, but more expensive than some other Nairobi options. Also the included breakfast is delicious.