I suppose it depends on how you do it. I worked from a beach town in Costa Rica for a month last year. I worked very well, being unusually productive (I think due to lack of stress and a change of scenery). I worked ~6-8 hours a day/5 days a week, and got more done than I had over many more hours back home. That left me plenty of time to meet and hang out with locals, so scuba diving, swim in the ocean twice a day, cook with local fish and ingredients, make new friends, etc... It was fantastic!