I've had several surgeries in Mexico including RNY, medical tourism is not for everyone but it was the best decision I ever made and all great experiences. Echoing the ladies sentiments above... RESEARCH! Be aware there are good & bad Dr.'s in every country and if your insurance won't cover the surgery chances are if you have complications they won't cover those either.
There is a Mexico Forum here on OH. Hit the forum drop down screen above to locate it... not sure how active it is but maybe message some of the people that have posted and ask them some Q's most of us are very willing to share our experiences.
You are welcome to read my blog
www.theworldaccordingtoeggface.com for my medical tourism experiences. I had RNY in June 2006, plastics in October 2007 & March 2008 (maybe read those posts from around that time for tips, what you might expect)
Best wishes in your research.
~Michelle "Shelly"