Shirts are really cheap, which is most of my dry cleaning. If you have a tough stain, they are likely to say they can clean it even with a low chance of success. It's not that they are dishonest - their Asian culture tells them that they are losing face if they can't meet your request. Keep this in consideration and encourage them to be very honest.
For normal, everyday cleaning they are a lot cheaper than the other people in town, and they are pretty fast if you need it right away.