To me, socionics is filled with deep insights that seem to gel with my personal experience, but there are certain areas of the theory I'm still intensely skeptical of the validity or usefulness therein. In general outline, I would say socionics works fairly well for me and the people I know well, as individual types, but I vacillate on other's typings enough that it's hard to really say the interrelationships fit together except with some I know.