After chasing my tail for a couple of weeks, by George I think I get it... mostly.
SOBI2 controls all of the directory listings but just the directory listings. Everything must be set to free.
AEC control all of the payments AND the membership levels. (Your do not want to have to manually set to Author or Publisher - sobi2 does this for you!)
I only have this running with three membership levels right now because I do not have ioncube on my host to allow advanced usergroups. Free Basic at $150/year or $15/month Pro at $247/year or $24/month
Some customizing of the Entry form, Vcard and Details templates must be done in SOBI2 - but it cannot be done without a query to AEC to determine the subscription the owner has.
The AEC - SOBI2 - AEC workflow looks something like this: