Hallo Pannenheimer,
I just tried USE_AABB, but there was no difference. I may go back and try trace and ent_move, just to see if it works. That's not a bad idea.
I've made another video showing how the panning is causing my entity to get temporarily stuck, which makes the movement very choppy:
http://www.youtube.com/watch?v=ardKYaVstmA