Should I get a HDB or bank loan for my bto?

HDB because you can change to bank loan anytime. Initially HDB loan also requires you to pay a lower downpayment.

HDB loan is safer.

It depends on your financial situation. A bank loan right now is more attractive due to the lower interest rate. However, I feel more comfortable with a HDB loan mainly because HDB is more flexible in terms of repayment if somehow unfortunately you run into cash flow problems and lose your job. I have met many people who are struggling to pay off their bank mortgage and have been brought to court by the bank.

I'd take a bank loan largely due to the primarily lower interest rate environment right now.

If your loan interest rises after the lock in period, you can refinance with another bank.

For the same budget, you can then repay more of your principle. For example, if you were paying over 25 years; $1.2K/mth for your HDB loan, and a bank loan with a lower interest means you only need to repay $1.1K/mth instead, then you can take a bank loan and repay $1.2K/mth, effectively meaning that your loan duration can be shortened to say, 22 or 23 years (didn't do any detailed maths, but you get the idea) and you'll be able to pay off faster.