Yes, that is certainly good. Even so, it is vitally official, for instance with letters being forced to do with legal issues. Fewer official plus much more common is "Expensive Sir or Madam:" (Notice the usage of the colon; "To whom it could worry:" also need to use one particular). https://lawfirminkarachi97266.theisblog.com/36842945/a-secret-weapon-for-criminal-lawyer-in-karachi