helped me in the following ways:

1. understand family relationships better
2. helped me find an s/o who is more compatible than my last
3. helped me depersonalize when i'm in a problemmatic relation with someone (still don't know how to communicate well with such people, though)
4. helped me understand my own needs better
5. helped me pinpoint why i would have certain kinds of problems (polr stuff) and how to work around this
6. helped me understand some reasons why my marriage failed and de-personlized the divorce

on the negative, it's a little bit limiting. people aren't types. and duality can be hard to find, so applying duality is harder in practice. socionics would have you believe that duality is needed in order to function well. some of us are here spiritually, to experience a flowing life without many obstacles psychological and otherwise. others of us are here to experience more struggle and strain - i believe there is a meaning to this which supercedes socionics.