Very unreliable. I spent nearly 5000 yuan to sign up for the diamond edition. There is no class group. Wechat has only one one-on-one teacher. I send a video link every working day. Problems are basically answered late or not. I don't bring projects. I just watch videos on a certain platform. This video lesson is only worth 50 yuan. It is said that the follow-up update video can be watched for free. I want to ask how I know there is an update, and I found that the teacher WeChat who signed up at that time was no longer used.