Had booked the Palacina for a week at recommendation of colleagues but stayed only two nights as i found the room unbearably stuffy. In most respects I agree with the other reviewers - the hotel is lovely, good restaurant, spacious suites, etc. But even if you want to sleep with the windows open (and Nairobi does cool off nicely at night), there is no cross ventilation in the room, and I found it far to stuffy to sleep. There is no fan, nor any air conditioning or other temperature control. Management did on request bring me a large portable air conditioner/fan unit, but while it gave me much needed circulation it sounded like a Boeing 747 taking off. It's really a shame as this is otherwise a very nice hotel, and the problem could easily be solved by installing ceiling fans in the rooms.
Other downside, if you have business in central Nairobi, is that the location is a bit far out and traffic can be quite bad, especially at rush hour. But if neither of these issues phases you, the Palacina is otherwise to be recommended (and is a lot cheaper than the "business class" hotels in downtown.)