My parents recently came to the US in that airline. They said that the flight was on time and ok but customer service was horrible and if you need some directions in airport, its a nightmare.

1) No english speaking people in transit.
2) I paid extra for their vegetarian food, they got none so the steward took out meat and served them rice and some veggies.
3) If flight gets delayed even for 24 hours, they don't care.
4) You have to transfer luggage three time. As for my parents, it was in KTM, Kunming and Shanghai with final destination to Los Angeles.

I recommend you have an app which translates english to chinese or vice versa and you should be good.