What is Reddit's opinion of Hong Kong Taxi Cards?

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my then-bf/now-fiancee (got engaged there!) grew up there (he's American, but his parents taught there for a number of years), and I got to travel with his family while they taught summer school at an international school. I got to volunteer and do some photography for the school, but I also got to do a lot of sightseeing. He'd like to eventually move back there, so I may actually be moving there in a few years! Aaah! I've been missing it pretty hardcore lately.

We were staying in the Causeway Bay area, and one of the things I loved was how close all these great things are. Fantastic noodle shops and restaurants of every possible cuisine within blocks, 7-11 right across the street for those late night snack needs, cool little stationery shops, and there was an MTR station right on the corner. Before that trip, i'd never used public transportation (except for this one trip to NYC when I was really little, so that doesn't really count), but after a few days, I was totally comfortable with the system and could get around the city by myself with no problems.

Edit: if you don't speak Cantonese, there's this app that you can use to tell taxi drivers where you want to go (I know there's an ios one too. just search "taxi cards") https://play.google.com/store/apps/details?id=hk.techmax.taxitranslator