The stock could go up at the time of split or it can drop slightly and then take off. The latter happens quite often as in the case of Coca Cola Enterprises (CCE)when it split recently. It dropped to the $19 range after a 3-1 split and then took off into the mid $30's. I don't think you can go wrong on this stock, now or after the split. Does anyone still have any answer about the foreign tax or is there such a thing.
In Mexico, by law, we don't pay capital gain taxes in stocks bought and sold in the stock market (It doesn't matter if you are a Mexican or a foreigner). There is not withholding by authorities or by stock brokers. However, remember that the US govt. charges taxes to Americans or US residents for all their worldwide income, it doesn't matter where you made the profit. You have to declare the capital gain to US authorities. You can check for more info in the web site of the IRS "www.irs.ustreas.gov"
KOF just announced a 3-1 split on Jan 16, payable on Jan 28, and the stock is optionable. The company rank 3rd of 17 in Beverages-soft industry, and earnings per share estimates rose 37% from last quarter.