Try to answer these for yourself:
Do you plan to commute, or live there?
Are there any employment options in your country where you'd wish to live?
What is your impression of the book?
Do you believe the overall experience at that particular airline is substantially different from the other China mainland ones?
The first-hand experience is varied. Those who left, sometimes in anger or feeling betrayed, have a different one from those who stay - beauty is in the eye of the beholder. Check safelife's post here, he admits having returned to Europe with no hurt feelings.
Public info:
- ground travel time to PEK where international connections are in abundance is 2 hrs with margins included, 80 USD one way in a private taxi.
- Sanya base for the A320 was no longer available 2 years ago when I did check on them, factually these days it is not even a destination of the airline anymore (true, the OP however asks about Haikou on the E190, that works)
- nice places to stay in Tianjin are just below 700 USD/m all included
- there are only one or two other airlines offering 3/3 to Airbus newcomers
AFAIK in PRC, and both are HNA group anyway
- the contract is 4 years, many think for a first taste 3 or 2 is the safer decision in case you wanted to stay in the area, but needed a change of the operator
- the salary is 800-1500 USD / month higher than anywhere else in China for the same type of vacation plan.
- HNA group is selling assets left, right, and centre. Full airlines or significant shares of included. The future could be different than expected rather significantly, or not.
PM sent. Which type do you fly?