I think students' opinions carry far too much weight in China. Any foreign teacher can be history throughout the Chinese edu system because of this. Although teaching in more developed parts of China, or for privste employers throughout the country, carries more risk of dismissal due to poor student assessments of classroom teaching, the state sector is not safe in this respect either. That's why I head for the hills. In backward areas, it's harder for schools to replace you fast if they want rid of you. Here I am a big fish in a small pond, and the worst scenario for me would be a job for a whole semester, having to terminate my contract early after mutual agreement that didn't lose me any money and perks for that semester's teaching. Then I can move on to another backwater. Work only in the public sector in a backwater, the best way in my view. Employers there have far fewer options - that's great for us!