Actually sp/so's prefer to not openly talk about prosperity. The first instinct is held too close to heart to be so careless with it. What people do instead is implicitly signal about their first instinct needs (and these signals are read correctly only by those who share their first instinct). There is even a sense of annoyance and dismay if someone is talking too openly and directly about issues of the first instinct. For example sx/sp would rather make sexual innuendoes instead of openly talking about sex. This is very different from sp/sx who will readily discuss such topics, much to sx/sp's discomfort.
This applies to sp/sos and so/sps. So/sp is the one likely to openly talk about their prosperity: home ownership, recent acquisitions, trips and vacations to lucrative places, dining at expensive restaurants. Sp/so's as a rule don't openly talk about this but indirectly signal of it (via gift exchange for example). Instead what they prefer to openly talk about are topics pertaining to their second social instinct. One of my best friends is sp/so 6 and most of the time she talks about topics of social justice and politics (things like the poor state of our schools, the military-industrial complex, wikileaks, etc.) She rarely talks about sp-issues, and when she does it is only in very direct and immediate sense, when these issues directly concern her.
It happens with any stacking. The second instinct is a flexible, explicit, creative area while the first one rigid, implicit, and approached in concrete manner because it is matter of life and death and primary neurosis for the person.