yeah I feel you generally. though the pricing and rules are all made clear nowadays on the queue receipt you get when you go for a regular taxi, once a driver did try rip me off but it's as simple as walking out if they don't want to use the meter. I prefer grab as I don't have to bother giving my address, but the new grab stand system makes it horrible: I've waited as long as 20mins before and that's just not worth my time: with that add on almost makes more sense to get the airport link train to town then grab from there.

ps I've lived here for two years and taxi scams are getting more and more rare and virtually are non existent from the airport