We just stayed here for 1 night between safaris and really enjoyed our stay.
The service was excellent, smooth check in, porters dealt with our luggage most efficiently and security was good. Although this is a good 5 star hotel no one seemed concerned that we looked on arrival like we had just stepped out of the bush....which we had!
The triple room was fantastic, absolutely huge, nicely decorated and furnished with a wonderful bathroom (something much appreciated after being out in the bush!).
The location is very central and our room faced the busy street below, but to be honest the traffic noise really didn't bother us.
We ate in the upstairs restaurant near the rooftop swimming pool and the food was good. It did close at 21:00 and even though my son decided on dessert after they had closed and all other tables had emptied, the waiter went downstairs to one of the other restaurants to find him some chocolate cake!.
The buffet breakfast was served in the Thorn Tree cafe and was a good typical hotel breakfast.
In my opinion probably not the place to stay if you are wanting a taste of typical Africa, but great for a short taste of luxury.

Internet booking fast and simple.
Airport pick-up no problems. Though the mini-van's air con was broken. We could not get into the hotel drive due to the parked cars, so walked from the street and thru the mid-day crowds. Check-in. Low on staff, phones answered, bit of a mess really, after a long flight seemed two girls were trying to do everything but getting no where, key given but no directions on where to go....this was the case every day, better to ring from the room!
Room: clean but tired, bed had a big sag on one side. Bathroom clean, but a little tired. Mini bar well stocked. Coffee & Tea in room. No power outlets that worked, apart from the electric kettle! WIFI very good.
FOOD: Breakfast average. Pool bar good. Room service good. Thai restaurant very good.
SECURITY: on every floor, and very helpful.
STAFF: All with out exception, pleasant attentive and helpful
Late checkout: OK until midday.
All up, compared to the other Nairobi hotels, for the price very good.

We thoroughly enjoyed our stay at the hotel. I was there with my wife and all was good. The staff were great, even got my room upgraded! Nice 5 star hotel.

Stayed for almost a week in Nairobi and selected the Stanley as a luxery hotel. That's what it is. Safety measures are taken and the rooms are very nice with television, minibar, water heather and coffee machine. Breakfast is nice as well and the location is great.

However the people at the reception stole my credit card details (this was the only credit card payment I did in Kenya so I'm sure it happened there). At home I was unhappily surprised with all kinds of expenses. Including tickets from Europe to America of more than 1600 euro's and lots of other things. Remember that I had to advance this money before getting my refund.

Also remember that Kenya is very unsafe. People we met who live there warned us not to go out in the evening. Even crossing the street of the hotel is dangerous. Take lots of precautions.