I've seen the recent short term endowment post : https://blog.seedly.sg/singapore-life-short-term-endowment-plan and therefore wonder if it is worth buying?

Do bear in mind that if you commit to a short term endowment plan, you absolutely cannot surrender it until the the policy matures, or you will lose money. 3 or 5 years, while not extremely long, is still a period whether you will have no access to this money, and hence you need to consider if you will have enough emergency funds to meet your needs during this period. I'd personally opt for the 3 year one to give myself more flexibility, unless I absolutely can live with not having access to the money for 5 years.

Whether 3 or 5 years makes sense for you depends on your objective. Do you see yourself needing the cash after 3 years? Going through policypal gives some policypal rebate to use for their other products or can exchange for some discount. You can see what is available in their app.