The Riad itself is wonderful. It is a traditional house, with four rooms off a balcony level. The room we stayed in was small but very comfortable and also very safe - lockable cupboard provided. The bed was comfortable and warm (we stayed in November) but there is also air conditioning for the hotter months. The bathroom was spacious with great facilities, and plenty of towels.
The cleaning of the room was second to none, and the hospitality offered by our hosts was fantastic - we were always offered a cup of mint tea in our room, and although we didn't take them up there were plenty of offers to arrange tours and visits for us. We were even given gifts as souvenirs when we left. Breakfast was delicious and traditional - pancakes and fresh bread, jams, coffee and mint tea.
Its true that the Riad is difficult to find - but only 20 mins walking from the square. Best way - get taxi to the Kasbah Mosque, then take first left on the Rue de la Kasbah, follow it round to the right, through a market and on to what appears to be a dead end, but where the riad can be found in a drive on right.
Late at night the walk can feel intimidating through the back streets and this would be the main negative, but we didn't have any actual problems - some reviews have mentioned drugs but we saw nothing like this. The people we did speak to (to find the riad) were friendly and helpful. Also during the day it is an opportunity to see some real Marrakech life in the market.