I notice that the adaptive skin I get from zSpheres is not always symmetrical even though I used symmetry when creating the zSphere armatures. Am I missing something?
Sometimes this happens. It is typically when you don’t have a perfect symline that can be used all the way down a body. Typically this will happen on the legs of a humanoid character. If symmetry is extremely important for your model then I would either fix it with a quick retopo in zbrush or use goZ to take it into another application and fix the sym line, mirror it, and bring it back into zbrush for the actual sculpting process.
Hope this helps.