http://www.socionics.com/sta/sta-1-r.html?

what are your thoughts on its validity and accuracy? what makes it better or worse than a run of the mill keirsey test (or anything else moderately respectable)? i've seen some odd and some accurate results come out of this thing, particularly ENTP and ESFJ interchangeability, and INTJ IxxJ. so are my diagnoses wrong or is this test kinda haywire?