Small question in music domain: if, for example, you have been hearing a wonderfull concert from a russian master player, can you tell him "молодец" or is it too familiar? Or, in this context, is it okay?
EDIT: INFO: I finally asked a russian friend. She said it was informal, and used for someone well-known, or if not for someone hierarchically inferior... So "молодец" is obviously not a neutral expression! Thanks a lot to all for your help!