The sticks are solid and work great but one of my sticks seems to have a manufacturing defect in that the part of the sticks with the threads is too long.  It was difficult to seat initially and then to unseat when I was breaking it down.  Because it was so tight I had to grab the head to undo it so go gunk all over my hand.  When I compared it to the others I noticed that the threaded section was longer than the other sticks.  None of the other sticks has this problem.