We did DPS-SIN recently with Indonesia AirAsia. We had 2 rollies and 2 small backpacks. We did pay for one 20kg checked luggage for just for peace of mind, since one of them was 13kg, and the other was 8kg (which they would let slide on other LCCs like VietJet, but it feels like >10kg definitely means needing to check it in). At the check-in counter, they only weighed the bag that was going to be checked in. The staff member seemed really lax here, likely because we already pre-paid ahead. We did see a couple groups re-packing on the side since they were likely weighed by surprise.

One thing to note though -You can check-in 10 days in advance and obtain e-boarding pass (not sure if it's for all flights / airports, but this seems new since the last time I flew with them). DPS gates (at least the remote gates in 6A-6C) don't even have weighing scales, so you can probably avoid needing to pay for checked luggage at all given that you can use an e-boarding pass at this airport, and your rolling suitcase is of reasonable size.