Our group of ten Americans visited Stone Town in mid February 2016.  We contacted Hamza Mzee by email beforehand and asked him to meet us at our hotel.  He arrived promptly and explained what he had in mind and how long it would take.  We learned so much and had a wonderful time.  Hamza kept track of us all and helped us find the things we were interested in without being hassled by shopkeepers and people on the street.  We never could have covered that much ground or learned as much on our own.  I would highly recommend him as a walking tour guide.