I have used them for years and I have never had any problems with them collapsing during use. They make two models. The 9-17 foot (5lbs) and a 6-12 foot (3.25lbs) model. I normally use the longer pole because the extra length provides a further reach that is needed when poling from the center position of the kayak. As for storing it when not in use, i normally lay it just inside the outside rail . If that does not work u can install a bungee holder on the outside of the yak. Here are a couple of pics for examples.
Here is an example of the bungee
