Different brand has different "loyalty" benefit. Hence, if you keep changing brand, you cannot enjoy the same level of benefit as compared with someone who keeps to one brand. For instance, SPC cards' discount percentage is dependent on your previous month's usage for that brand of petrol. Shell gives up to 5% discount for selected UOB credit cards. Other brands give more discount for other bank's credit card. Unless you have all these banks' credit cards, you will enjoy less discount.
On another note, my friend and I experimented and found that when we mix brand but keep to the same grade, we got better FC. However, some people advised against mixing as it may be bad for the engine (not sure true or not). So, we did not mix brand that often.
Only SPC has loyalty scheme which is based on previous month usage. Previously NTUC Udrive card also has something similar with Citibank Esso Mobile priviledge card with 6% discount and 7% rebate on next bill. Sadly, that 15% discount has ended and they replaced it with NTUC Plus card, an OCBC Card with 5% additional discount for Caltex. Same for HSBC card. For Esso users DBS Esso Gold Mastercard gets immediate 5% off. For Shell UOB Signature/Plat card or Citibank Dividen cards gets 5% off. Prefer to use UOB cards for Shell, don't need to wait for the quarterly Dividen rebates. For SPC, if you are a Safra member, gets 5-8% off next bill and you would have received by now their $3 discount vouchers which can redeem for every min $40 top up. The vouchers expires end April. If you pay with Citibank Div, have another 5% rebate!
I had started with Shell 95, since all 95 the same price why not go for the perceived premium brand? I switched to Esso 95 when Udrive discounts are good, it gives me improved mileage and the Cheers store is better than 7-11.
For the next mth, I'm on SPC 95 til my vouchers runs out.
Then it's back to Esso 95 paying with DBS Esso card since it gives me best mileage, better shopping experience and rewards.
I do not subscribe to the idea that mixing brands petrols will harm engine. Cars engines are designed to be robust for daily use and handle efficient combustion of fuels for power. The Octane levels determine how much power you get. It's personal preference which brands you use. With petrols all being the same price across brands and grade each time they up the prices, the discounts offered becomes significant factor in your buying decision. Whichever brand that gives you the best driving experience, mileage, discount and rewards will give you the most bang for the buck!
