The BSE India Sensitive Index is the best-performing among BRICs equity benchmarks, increasing 13 percent, compared with a 2.6 percent gain in Russia's Micex Index and a 2 percent drop in the Shanghai Composite Index. By comparison, the Standard & Poor's 500 Index is up 11 percent this year, while the Stoxx Europe 600 Index has climbed 9.1 percent.

"You've seen a rotation in the leadership based on rate of economic growth," said Paul Christopher, the St. Louis-based chief international strategist at Wells Fargo Advisors, the third-largest U.S. brokerage with $1.2 trillion in client assets. "If you go back as far as just 2009, you'll find people buying the BRIC story in a big way, and probably over-buying the BRIC story."

Pouring In Money

Investors poured about $67 billion into BRIC stocks from 2001 to 2010 as they beat the S&P 500 by 281 percentage points. They withdrew about $15 billion last year, the most on an annual basis since at least 1996, according to Cambridge, Massachusetts-based research firm EPFR Global.

Still, equity funds investing in the MIST nations haven't been immune from global growth concern. While investors added a net $104 million to funds focused on Turkey and $123 million to Indonesian funds this year through Aug. 1, they withdrew $1.33 billion from South Korea and $115 million from Mexico, EPFR says.

The MIST nations each account for at least 1 percent of global GDP and are likely to see that share increase this decade, O'Neill said. Of the four countries, O'Neill said Mexico and Turkey are the most attractive at the moment.

Low-Cost

Mexico is increasingly competing with China for manufacturing as costs climb in the Asian nation, O'Neill said. Mexico's economy grew 4.6 percent in the first three months of 2012, the fastest pace in six quarters, on increased shipments to the U.S. America Movil SAB, the wireless carrier controlled by billionaire Carlos Slim, the world's richest person according to the Bloomberg Billionaires Index, was the top holding in the N-11 fund at 7.9 percent at the end of June.

Brazil, which grew at an average 3.7 percent annual rate from 2000 through 2010, trumping Mexico's 2.1 percent expansion, is forecast to grow less than 3 percent for a second straight year in 2012, according to the median estimate of analysts surveyed by Bloomberg.

Wells Fargo's Christopher advised investors to sell stocks in the BRIC nations at points in the first half of the year and recommends buying equities in Indonesia, where economic growth has exceeded 6 percent for seven quarters. Plans by the government in Southeast Asia's largest economy to build railways, airports and seaports to bind its islands closer together are helping to counter a slowdown in European demand for commodities exports.