My only experience with mule deer was on a whitetail hunt in Kansas. The area had seen a ton of pressure the week before we got there and the whitetails were simply gone. The only deer left were mule deer. There were not any mature bucks in the groups but there were some older does. We could jump them out of the same spot every day, and they would always stop and offer a shot after being jumped. To say I was not impressed with mule deer at that point would have been an understatement.
I realize that a mature mule deer buck, or probably any mule deer in open terrain would be a tougher hunt than these. But even a whitetail fawn would of been tougher to kill than the 2 groups we were seeing every day.