First off, be aware that when they give you a price quote, the price is for a 45 minute lesson but the lessons are really 90 minutes long so you'll end up paying double. They're still competitively priced, but I thought that was really deceptive.
I have the impression that people's experiences with this school depend on which instructor they get and whether or not they speak Chinese. My instructor's English wasn't great, and he wasn't very good at explaining parallel parking, three point turns or maneuvering in reverse. I basically had to figure those out by trial and error. He was also extremely unfriendly; he didn't even introduce himself, or say hello or goodbye, and his comments were often more distracting than helpful. For example, if I was waiting for oncoming traffic to pass so I could make a left turn, he would point out a poorly parked car on the other side of the street and make me look and acknowledge it before finishing the turn. On multiple occasions we got stuck in the middle of an intersection after the light changed because he told me to drive through the intersection when there was traffic backed up on the other side, and under pressure he mixed up directions like 'forward' and 'left'. He didn't really hear my questions either, and never said one positive thing.
On the plus side, they give you lots of experience driving in traffic and the instructor pays very close attention to detail. He'll correct your smallest mistakes, which definitely helps you improve. However, his poor communication skills made the entire experience more stressful and I failed my first road test, which he was half an hour late to. I'm going to find another school to help me practice for the second.