Charles Sizemore, a portfolio manager at Covestor, agrees that the prospect of an open energy market offers great opportunities—"just look for anyone who could benefit from increased oil development," he said—but argues that sectors across the board deserve a look.
"You can't overstate the benefits Mexico enjoys through NAFTA and by being next door to the U.S.," he said, adding that the country appears to be growing only more attractive.
As labor markets in China and elsewhere mature and wages rise, Mexican labor becomes more competitive even if still more expensive. "What you lose in higher wages you get back in faster, cheaper transport and the benefits of a known, friendly territory," including an abundance of bilingual talent, he said.
Luxury bedding maker Kluft is one U.S. company investing in the Mexican market, and high manufacturing standards are one reason. In Mexico, CEO Earl Kluft said, the company "is working with a trusted partner capable of the craftsmanship these luxury products require. That's not the case everywhere. For instance, Kluft finds it necessary to export American-made mattresses to China."
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Kluft says that an increasingly stable economy and a growing middle class make Mexico ever more attractive to companies like his, adding that he expects the luxury market to grow at 10 to 15 percent annually. Mexico's economy is expected to pick up steam next year to grow at about 4 percent, according to the finance ministry.
"Direct investment is what every emerging market wants, more than the hot money that rushes in and all heads for the door at the same time," said Sizemore of Covestor.
Global investors are keeping an eye out for "predictable, reliable, secure domestic institutions," added Karolyi. Mexico's increasing success in building them "may indeed be why we haven't seen the intensity of capital outflows there," he said.
—By CNBC's Matt Twomey. Follow him on Twitter