We were on a family holiday of 11 people and this was booked by our son in law who stays here regularly on business and has found it a good place to stay.
For our 2 day stay to adjust to the time zone before a 6 hour drive to Kruger for our safari (another review) the Davinci was a very clean place our room was very spacious and clean every day, the front doorman in the bowler hat who greeted us every time we stepped from a taxi was polite and always had a smile (as did all the staff) the chap near the elevator always beat us to the up button :)
The hotel is part of the Mandela Square and Sandton mall buildings so there is lots going on near and around you.
Around the square there are many restaurants with various cuisines for all tastes to enjoy I also believe the gautrain is very close also.
We never had a problem with our room it was spotless and all amenities replaced each day.
I would recommend this hotel everyday, mind though as with any hotel they can have their bad and great days whether 5 star or b&b level the staff are only human. Also I imagine that management look at all the reviews and are always adjusting to correct those problem areas.More