For those who are looking for cash back on Debit Card purchase and NETS, do take a look at SCB XtraSaver account: http://www.standardchartered.com.sg/deposits/xtrasaver.html
I signed up for it and due to my numerous online purchases, the cash back is pretty decent. 2% for MasterCard cash back and 0.5% for NETS cash back. Whenever my UOB ONE card exceeds 800 bucks, I will use this card to pay for all my purchases.
On top of that, I use NETS to pay for my UOB ONE bill at AXS machines. Effectively, I will be able to get up to 3.8% (from 3.3%) cash back on any purchase.
The only downside is you will have to maintain at least $6,000 balance in your account. One more thing. Never never pay with Debit Card at any Petrol station if you are not pumping petrol. All purchases other than petrol will still be counted as Petrol purchase and that reduces your cash back to 1%. Just found out today and I do not drive!
Just some tips to get some free cash!