There is a 2-part article that compares operators from Zalando, Crunchy, KubeDB and StackGres.io (unfortunately only in Russian, but Google Translate and its alternatives do job well nowadays)
All of them are being developed very actively, so I recommend defining your own goals and making your own tests (plus, maybe talking to developers on your own needs to see where a good match exists).
I am looking for advise of running Postgres in K8 along with Operator. Which Operator will be best for this solution? Is any company running the similar setup in Production?