Been using this card for the past 4 months now? But mainly the virtual card part of GrabPay. Not the physical card.
So I've been using my AMEX top ups into GRAB Pay and thus getting miles on my purchases indirectly together with the GrabRewards points.
In terms of overall UIUX, it is quite simple to use and straightforward to get what they are trying to achieve with the GrabPay mastercard, basically being the intermediary between all their services.
I was in Penang recently for a trip and realised that by paying with my GPMC, it was pretty straightforward to use the Grab Pay card itself rather than fumbling around with cash. And the exchange rate is also not too shabby.
Pretty straightforward, and clean style. Classic Grab.
Oh this is one bad part, you can't withdraw cash using your Grab pay card, but I guess what's the point, rather use it for your normal Grab Rides.
Bad experience with the devaluing of points, but other than that, I do think this one is here to stay for sure.