i rode a few of the various epics, the best ones were the older ones with the fox dampers, and the best of those were the earlier ones. the frame got stiffer as they got newer but the best shock action was the earlier 2002/3 models. i agree that the ones with the big knob on top were the worst as you couldnt get the right settings, it wouldnt seem to lock-out enough when closed, and would seem to open up enough when going over bumps. if that makes sense?
you have a good bike there. ride it hard, they are stronger and more capable than you may think........