There must be mixed reviews about Media Luna because it is not a luxury property. We stayed on the first floor. The room is adequate and clean. The bathroom is small.
I chose Media Luna because is was $100 and night, close to downtown and on the water. I think it is probably the best accomodation in Isla Mujeres with that criteria. We had already been to Mexico that summer (2005), and I was trying to do it less expensively (because our first trip was more expensive!).
We spent our mornings by Media Luna's pool and around lunchtime walked to North Beach for lunch and the beach there. We would come back to Media Luna mid-afternoon and stay out by the ocean or pool before going in to get ready for dinner.
We have also stayed at Villa Rolandi in 2001, and Na Balaam in 1994.