Thanks, that's good to know. I have my joints mirrored based on behavior as well. I wanted to ask someone about that because I wanted to see if that may have been part of the problem. I don't know very much about rigging, as this is only the third rig I've ever built, and the first one where I've tried making an IK/FK switch. Here are some images of my arm joints and their orientation.

A general image to show joint placement


The FK Chain


The IK Chain


The Skin Joints