Can't say so. Ocbc titanium is used more on bills. While for mbb2, Amex is not widely accepted and the MasterCard/visa is basically useless.

Having said that, what I do is:
- use ocbc for bills. Almost 100% 5% rebate
- dining, if weekends and accept amex, swipe Amex, else ocbc
- petrol, fill in on weekends, use Amex. Always can time it to weekends coz I dun drive frequent
- on weekends, if it's accepted, always try to Max out Amex rebate, since it's harder to find outlet that accept Amex.
- on weekdays, if it's accepted, use Amex for those spending not under dining, bills, groceries and petrol that can get ocbc 5%, since Amex 5x points is equivalent to 2.5%

In short, always try to max out 5% rebate (additional 5x points) from Amex first. It feels good when u can get 5% from ur normal shopping from Amex.

Last weekends, bought cosmetic for my gf, rm260 from parkson, swipe Amex, 7.5% is rm19, parkson give rm30 voucher for spending over rm250. So I got rm50 "rebate" for rm260. Good feeling! Not to brag, but its a good feel too when ur gf timed buying of cosmetic to this festive season since parkson always give away vouchers like that on such occasion

As for Payment(s) at BHPetrol, Smart$ Cash Rebates are awarded for transaction up to a maximum of RM400 (Per month per card account) at the cash rebates rate.

eH.... you can always try call in to cancelled the card the CS will offer you 5x transaction any amount or 1 single transaction of 100 or 200 i forgotten already
they will compensate you within 60days.
That's what i've done la....make sure you mention cancel due to GST
i'm using UOB one card btw