It's been a while, but I will answer some of your questions. I believe Danzan Ryu comes from the same lineage as what I used to study, Hakko Ryu which originates from Daito Ryu. From looking at the list of dojos on Jujutsu America, you are in very good company. Why? Professor Jay (Small Circle Jujutsu) is on there and so are a number of his students, instructors in their own right. I am sure that Prof Jay would not be a part of an organization that is suspect. As far as is it a good self defense style, I have a feeling that would have in large part to the dojo, instructor, you and how the classes are run. Since I believe it is more old school jujutsu, you will definitely be stressing pressure points, the meridians (sp?), and small joint manipulation, eg. wrists, fingers. Hope this helps.