We stayed for five nights at the Rebali Riads at the end of February 2013 and loved it. We were there for a Yoga retreat but combined it with a trip to Essaouira, a cooking lesson, tennis, swimming, sunbathing and even horse riding along the deserted beach - paradise.
Sidi Kaouki is a good 20 minutes from Essaouira by taxi if you feel the need for the 'big city' but we were happy to sample the local restaurants or eat at the Rebali.
The quality of the Riads is superb, real attention to detail and a genuine desire to make your stay as comfortable as possible.
Would happily go back anytime.