We have spent an excellent 5 nights at riad villa harmonie! We booked directly with Katherine after spending hours looking at all the different places to stay in Marrakech. From the start she was extremely helpful and this continued throughout our stay at the riad.
The riad is very close to the hustle and bustle of central Marrakech, we arrived late at night and prebooked a taxi from the airport with Katherine, we were pleased we did as the riad is well hidden and would be very very hard to find with no guide late at night! It is located at the end of a quiet residiential alley which has a couple of shops where you can by water, sweets etc

All the staff are extremely helpful and courteous, we left an iPhone in the room by mistake and we were relieved to hear that the maid had already handed it in to Katherine by the time we were able to phone her from essouaria later that day, which was a great relief as it could have easily disappeared never to be seen again!!!
As I said the riad is down a very narrow alley no more than 10 minutes walk from jeema el fna square and very close to the tombs and palace, we walked everywhere in Marrakech apart from a trip to the new town, and found it to be safe and a great way to see the city, just watch out for the traffic!!
The riad has been carefully decorated and the roof terrace is lovely and is a great place for breakfast to be served or a beer or glass of wine in the evening (the riad does serve alcohol)
We also ate at the riad one night and although expensive compared to most of the restaurants in Marrakech it was excellent, we also had the roof terrace to ourselves which made for a lovely evening.

Overall this is well worth considering if you are coming to Marrakech, we haggled the price of the room prior to booking with Katherine for 6 nights for a standard room. If you hunt around there are a number of websites which offer rooms in the riad for much less than is shown on it's website. The riad really is little oasis of calm from the hectic streets of Marrakech. The riad does have it's own website which does give a true reflection of the the place, it really is a hidden gem which has yet to be uncovered by the masses!! Oh yeah and it also has free wifi which comes in very useful