The last time, when they gave me the run around, I had to come back several times, and it seems like they were given me the run-around. Because of my extensive tourist visas, work visa, volunteer visa, etc, I always assumed they were given me the run around because quite obviously I am willing to pay an agent.
I have had the standard vision tests, and glasses replaced a few times here. It's certainly a lot less expensive.. You can always spend more but my last pair of glasses costs about $200/USD. In the US, ten years ago, that would have started at $200 and by the time I am done paying for frames, exam, lenses, lens extras, $500.