I had a great stay at the Palais Fès Yahya. Not only was the Riad a charming and well-located place, the staff are incredibly kind and welcoming. When you stay here you aren't just getting the benefit of the hotel. Fès can be difficult to navigate as a tourist, and the hotel is also useful for organizing other trips (e.g. guided tours, day trips). They use people they know, who are themselves honest (trust me - you don't want to get guides from the street in Fès!). As an added bonus, the restaurant on the terrace is quite good, and you can end up meeting other travelers there (it tends to be a friendly environment, encouraged by the staff).