Lake Osakis

My wife and I are talking about making a trip north next year to crappie fish. At one time I remember reading in Crappie World some years back that Osakis was rated among the top ten crappie lakes in the country. Any of you fellows up there care to comment on the quality of the crappie fishing in Osakis. We are both retired and can make the trip anytime during the year. If you were going to pick one week, when would you go - spring, summer, or fall? I have heard that September and October can be very productive. Thanks for any info, advice, etc.