Hello everyone, I am very new here. If I posted in the wrong place feel free to move or delete this.

I will often bw traveling to Asia, specifically China, to airports in Nanjing and Shanghai from California. (I mainly go to Suzhou a lot, but they don't have an airport).

To all China travelers, what frequent flyer program do you use? Also, what has the best benefits for being a higher tier in the program?