These are the conventional risk free Fixed Deposits but your funds will get locked up longer if you want higher yields. I cannot be bothered with such deposits.
Serves your purpose only if you want to park money offshore. If you have no urgent use just park in China. Use it as capital funding to convert to SGD as and when you require while earning higher interest rates in onshore China banks.
Actually the interest rates looks good if compared to Singapore but if you take into account of the real interest rate (interest rate - inflation rate) then it is not very impressive as China's inflation is higher than Singapore. However if your intention is to convert to SGD then this is where you gain advantage from interest rate differentials as you are spending in SGD. But of course subject to exchange rate fluctuations.
Do not underestimate the power of arbitrage and interest rate differentials. If not how I go for frequent jiak hong trips besides the additional Forex trading profits.