I stayed at Miraval in Jan/Feb 2013. I had a completely wonderful experience. As a few months have passed since my stay, I find that what I remember most fondly is the wonderful staff: warm, intelligent, kind. I participated in many of the activities and enjoyed them all -- the staff I encountered for the outdoor adventures and at the horse stables, and for yoga, are all lovely. The administrative staff was responsive and without exception went the extra mile to accommodate my requests. I loved the food, I loved the setting, I loved the atmosphere. I've been to Canyon Ranch twice, but I prefer Miraval, and hope to make it a regular destination.
My room was rather ordinary, I hope they will do some renovations soon -- I echo an earlier poster about inadequate lighting for reading, also the walls are very thin!