The slippage between the buying and selling rate is about 2.5%-3%. When you place this FCFD short term (<6 months), you currency has to appreciate for you to make money. Otherwise you will lose. If the FD rate is 7-9% and you place 6 months (3.5%-4.5% for 1/2 year), and assuming the currency is about the same as when you bought it, then you make a little.

Worth it? I don't think so.