I have a production operation there. To summarize as much as possible...there are an incredible amount of government policies which discourage foreign investment. Too many to list here, so do your research. IMO if the Mexico changed these policies there would be enough jobs there to keep the flood of illegals from crossing our borders.
The best approach is to partner with a Mexican citizen with management and business skills. One that you can trust and knows the "lay of the land". Also, locate in a town or city near the US border.
Notwithstanding the aforesaid, I have been very pleased with my decision to open shop there. Requires little oversight on my part...the people have a wonderful work ethic and trustworthy.