Here for 4 nights for a conference at Mandalay. Love the internal walkway and the street access as well when fresh air desired. There is also a free tram if walking is a challenge. I have stayed here last year as well also in the pyramid. Both times have been fine for me, room clean and smell is ok for Vegas. Not smokey but not the freshest thing I could imagine either. The amenities are getting a bit dated though I guess there are new rooms becoming available I assume at a higher price tag. Ground floor offers plenty of dinging and beverage options as well as shows (though I have no experience there). Would happily stay here again when needing to have proximity to this area. Elevators reasonably fast (4 on each of two of the diagonals corners, traveling an elevator that travels a slanted shaft is interesting the first few trips.
One of the nice thing is when spending the evening geocaching you can always spot the beam of light in the sky to find your way home.