Take both.
8% good for Lazada and Shopee. Not limited to weekend. But unfortunately for ONLINE transactions only.
Another consideration is SST charge, it is better to get a credit card in a new year.
Yes for Lazada Bill payment
- Unifi, Astro, IWK, Telco (except Maxis), Water, Electricity (except TNB)
- PB Mastercard and Lazada Wallet may give you more than 8% discount/rebate.
You can't use Amex to pay digital goods at Shopee App (this submodule is handled by Airpay Malaysia, sister company of Shopee Malaysia). You need to find a seller at Shopee platform to help you to pay the bills, of course there is a cost.
Currently some people (not all) may be able to use Spaylater to pay digital goods at Shopee App and some Shopeepay merchants, with 1.5% upfront charge by Seamoney Capital Malaysia. At this moment, you may use Amex to settle Spaylater debt, so around 6.5% savings if 8% CB from Maybank Islamic.