I never have, only because I think nobody ever turns any in, and if someone did, one of two things would happen: 1) a young teller wouldn't recognize them as legal tender and refuse them, or 2) the teller would call a supervisor over, the supervisor's eyes would get as big as saucers and the coins would go home with him/her.
Stranger things have happened but about the best we can all hope for is a solid roll of silver like kalpinro recently acquired.