I've a user with access to one model through the membership of a group (update priviligies on the model and row security using hierarchies) and another model (update priviligies) directly via the user. This gives the user two models to choose from in the
explorer model selector.
Once the user has entered the explorer with model#1 selected and then comes back to the MDS main page and select model #2 to explore he's directed to model #1 anyhow. It isn't possible to explore model #2 even after closing IE and selecting model #2 again.
I've been running the SP 'UpdateSecurityModelMemberProcessRebuildModel' on both models.