The little I know about Isshin ryu boils down to it being a style that is heavy on the basic moves. They strongly value a good side or front kick over a flashy jump kick. They have 8 katas. It is a pretty hard core style. Isshinryu came to this country with the marines who came home from being stationed in Okinawa. So think about how hard core marines are when you think of Isshinryu.