I'm not retired, but currently I live in Costa Rica. It is a truly beautiful country and the people are very warm.
Pros: very diverse plants and animals, fantastic climate so don't need AC or heat, housing is relatively inexpensive, some types of food are more affordable, people are well educated, too many fun things to do at low prices, like national parks, theater, etc.
Cons: some types of foods are more expensive (and not what you would think . . . like candied nuts are more expensive), in the bigger cities petty crime is enough of a problem that there is security guarding all building entrances and many residences or business have spikes or razor wire along the tops of their gated or walled homes or compounds.
I enjoy it here and the biodiversity alone would draw me here for life. The biggest reason I probably won't do it is that I'm a chicken heart about seismic and volcanic activity.