How about Shenzhen Zhongpei Zhidian Education Technology Co., Ltd.?

This is an institution that provides adult education. It has branches in many cities. The company is not small. Should do well.

The tuition fee is not bad, overall it is not high, just average.

As for the teaching effect, my friend applied for it there. He applied for 4 subjects in October last year and passed 3 subjects. Not bad. If you are interested, you can go and experience their trial classes yourself.