If you got one or more iOS devices that you want to play content from on your TV then I think 600 CNY is a very reasonable price. Sure there’s alternatives like for example Chrome cast which are cheaper, but Chrome cast is another proprietary streaming protocol and don’t work as smoothly with iOS devices as AirPlay does.
I don’t have one at home but I use Airplay on Apple TV’s at work a lot. They work fantastically, streaming from your laptop to Apple TV is incredibly seamless and easy.