I have a hard time to distinguish them. I think I'am one among the both, but I can't decide wich is the one. I'm sure I'm a sexual 9, I've read that the sexual nine is called the "union" type and that's totally fit with me. The social nine is called the "peripheral participation" type who can like activity with group but to be disengaged at the same type and move toward asociability, and the self-pres 9 is called the "appetite" type. I think I fit more with the social variant. I'm the type of person, for example, who eats just because he's supposed to eat according to the social ritual. But who eat just what is necessary, and no more.
I've had some episodes of compulsive fooding, but I think it was more a form of narcotizing associated with excess (wing 8) rather than a real interest for material consumption. Actually, I think that I got bored for everithing associated with self-preservational stuff. I've doubt to have So in second rather than Sp because I'm clearly introvert, but there's some introvert So here (Bubbles, Ayo...), so I guess it does'nt matter. But I still a little hesitating, so I would be interesting with more details or information about differences between Sx/Sp and Sx/So.