I haven't used a variety of styles, but as I mentioned I find my simple wooden staff to be very useful. I use a staff that's just a couple inches shorter than I am and is around 1" in diameter (a bit more at the top, a bit less at the bottom).
I find one of the biggest advantages to the simple staff is the fact that there isn't a dedicated hand grip area; the length of the staff between the ground and your hand is infinitely variable without having to do anything other than shift the position of your hand.
There are many situations - crossing a fast stream, walking along a narrow board-walk or a narrow path across a steep grade, going up or down a steep hill - where holding staff somewhere other than the position you'd normally hold for hiking along a flat trail is advantageous.
Similarly, I've used it to help other people up a step grade by holding on to one end and getting them to grab the other so I could pull them up.
I think it's in these type of situations that the staff shines; that and when you & a buddy are crossing a stream and get to recreate the Little John v. Robin Hood scene
.
While I had been considering something collapsible that I could stow away if I wanted to and would be easier to transport in a full vehicle, the above reasons make me think my no-cost wooden staff is worth sticking with.