Pros
Thorough orientation leaves you well equipped for both teaching English and living abroad, even if you have little experience with either. Options for Chinese language class for beginners. Orientation also provides an excellent and close-knit community of fellow teachers, though you may be scattered to different cities. Support continues to be available throughout the school year, although you don't need to engage with field staff much if you don't want to.
Cons
Your salary will be significantly lower than that of other foreign teachers. It's enough to live comfortably, but it won't do much for your savings or fund your travel. The trade off is better training and support than almost any other foreign teachers get in the area, and the rest of your salary helps fund WorldTeach's operations in other countries where schools can't afford to pay teachers as well as China can. For me, that was a worthwhile trade-off. For some people, it may not be.