According to the query, the first service network displays:

1. Good service quality: As a large domestic airline, China Southern Airlines has always paid attention to the improvement of service quality. The crew of China Southern Airlines have undergone rigorous training and can provide professional and efficient services. In contrast, the performance of Shenzhen Airlines in service quality is not good enough. The quality of the crew of Shenzhen Airlines is uneven and the service attitude is not enthusiastic enough.

2. Safety: China Southern Airlines always pays attention to safety in production and provides high-quality safety guarantee for passengers. After strict training, the crew of China Southern Airlines can master various emergency treatment methods to ensure the safety of passengers. Shenzhen Airlines' safety performance is relatively poor. The quality of the crew of Shenzhen Airlines is not high enough, and the ability to deal with emergencies is not skilled enough.