A post-covid update...
I recently completed a one night stay here. It's really a great hotel. I think the location in Westlands is fine. You can walk to the nearby mall, and there are a few other things around.
As a Titanium, I was upgraded to a suite. I chose a bottle of wine as my welcome gift, but you could also choose some other sort of Kenyan souvenirs. Everything is new, well maintained, and comfortable.
The executive lounge was great. It's open all day, and the service is always very attentive. I thought the happy hour (1700-1900) selection was pretty strong. There are several beers, several spirits, and 5 wines to choose from. The food servings are good, and plentiful. You could accidentally make a meal out of it if you don't watch what you're eating. The cheese plate was of genuinely high quality. I believe they put sushi out most nights, but they didn't have it the night I was there. If you want to sit by the window, get there early, There are really only three spaces by the windows, and they go first.
Breakfast is in the restaurant on the 1st floor, and it is really good. They have a western, Asian, Indian, Mediterranean, and Swahili section. It resembled what one might expect to see in Asia, more than what you might expect in Europe. I especially liked the Indian section; they had a person making fresh dosas.
I was on an 11:30 PM flight that evening, so I valued late checkout. I was a bit surprised that they couldn't accommodate anything past 4:00 PM. I know they're under no obligation to do so, but that's something you'll often see in places like Nairobi with a lot of late night departures. They did; however, allow me to continue accessing the lounge until I decided to leave. While I was out on a safari and didn't get back to the hotel until 7:30, had I been around during happy hour, they would have let me enjoy it. My key was still working at 8:30 PM. I showered in the locker rooms by the gym before departure. Gym has great views and Technogym equipment.
I can't really imagine staying anywhere else in Nairobi. Like everywhere in Kenya, the staff here are just as friendly and welcoming as can be. Do make sure that your taxi/Uber/Bolt driver takes the tolled portion of the expressway to and from the airport. It will save you an immense amount of time.