Before you decide whether in Singapore or overseas, you may want to consider:
(i) Track record
Banks assess credit worthiness based on the years of operations in a particular country. If your company is a new set-up, you will likely find it difficult to borrow onshore in country of operation.
(ii) Interest Rates vs Foreign Exchange Risk
Interest Rates and Foreign Exchange Risk should be reviewed together. Interest rate is the cost of borrowing while Foreign Exchange rate is applicable when 2 currencies are in play. If the currency of your source of repayment (e.g. receivables) differs from your currency for your borrowings, then foreign exchange rate will come into play when it comes to converting one currency to another to repay your borrowings. Hence, you should weigh between FX volatility and interest rate savings.
(iii) Ease of remittance for loan repayment
If you need to remit funds overseas for loan repayment purposes, you need to check local regulations and requirements on remittance to said country. In most countries, interest payments relating to overseas indebtedness may attract withholding tax.