From Baiyun Airport to City (Tianhe) After Midnight

Hi, i will be arriving at Guangzhou Baiyun airport after midnight. Understand that the best option will be the taxi (meter). Anyone encountered any issues before? Heard that after midnight, taxi driver might ask for flat fee instead of meter. Or they may promise meter fare but when halfway into the journey, they request you to pay certain amount of flat fee else will just drop you off immediately. Thanks in advance for the advises.