I ordered another one today, and have had the same barrell nut issues as you guys. The cam can also suffer from stess fracture.(ie. they must break)
Maybe an industrial design engineer should have taken a good look at this.
There is a simple get you out of trouble solution should anybody break anything and want to carry on using the pole. The solution is not as good as the cams for locking the sections, but is simple and does work.
I've been promised some plastic bits with my new order, if i get them i'll put some pictures up and show you the very simple if all else fails solution.
If you look at other good examples of product design such as the clock work radio, or the dyson dual cyclone, alex has actually done incredibly well.