HI LC:Well just as in the old TV show folks move from one environment that they have gotten used to to another(city to country).

First there is the language, yes there are plenty of english speaking people about but it still isn't say Bobcaygeon.
There is a different pace of getting things "done" there also.
I worked in Mexico on job sites(and Africa etc) and one has to be ready for some culture shock.My wife and I liked Costa Rica and if we plan to run away from winter that would be my preferred landing spot.

Now some people thrive on adventure(I was that way in my youth) and I could see a Mexican retirement as the "gran aventura" to some folks.